summaryrefslogtreecommitdiffstats
path: root/widget/cocoa/nsLookAndFeel.mm
blob: cbee90f5810c6307e31bacc0d85aa63c707d3fed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsLookAndFeel.h"
#include "nsCocoaFeatures.h"
#include "nsIServiceManager.h"
#include "nsNativeThemeColors.h"
#include "nsStyleConsts.h"
#include "nsCocoaFeatures.h"
#include "nsIContent.h"
#include "gfxFont.h"
#include "gfxFontConstants.h"
#include "gfxPlatformMac.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/widget/WidgetMessageUtils.h"

#import <Cocoa/Cocoa.h>

// This must be included last:
#include "nsObjCExceptions.h"

enum {
  mozNSScrollerStyleLegacy       = 0,
  mozNSScrollerStyleOverlay      = 1
};
typedef NSInteger mozNSScrollerStyle;

@interface NSScroller(AvailableSinceLion)
+ (mozNSScrollerStyle)preferredScrollerStyle;
@end

nsLookAndFeel::nsLookAndFeel()
 : nsXPLookAndFeel()
 , mUseOverlayScrollbars(-1)
 , mUseOverlayScrollbarsCached(false)
 , mAllowOverlayScrollbarsOverlap(-1)
 , mAllowOverlayScrollbarsOverlapCached(false)
{
}

nsLookAndFeel::~nsLookAndFeel()
{
}

static nscolor GetColorFromNSColor(NSColor* aColor)
{
  NSColor* deviceColor = [aColor colorUsingColorSpaceName:NSDeviceRGBColorSpace];
  return NS_RGB((unsigned int)([deviceColor redComponent] * 255.0),
                (unsigned int)([deviceColor greenComponent] * 255.0),
                (unsigned int)([deviceColor blueComponent] * 255.0));
}

static nscolor GetColorFromNSColorWithAlpha(NSColor* aColor, float alpha)
{
  NSColor* deviceColor = [aColor colorUsingColorSpaceName:NSDeviceRGBColorSpace];
  return NS_RGBA((unsigned int)([deviceColor redComponent] * 255.0),
                 (unsigned int)([deviceColor greenComponent] * 255.0),
                 (unsigned int)([deviceColor blueComponent] * 255.0),
                 (unsigned int)(alpha * 255.0));
}

nsresult
nsLookAndFeel::NativeGetColor(ColorID aID, nscolor &aColor)
{
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;

  nsresult res = NS_OK;
  
  switch (aID) {
    case eColorID_WindowBackground:
      aColor = NS_RGB(0xff,0xff,0xff);
      break;
    case eColorID_WindowForeground:
      aColor = NS_RGB(0x00,0x00,0x00);        
      break;
    case eColorID_WidgetBackground:
      aColor = NS_RGB(0xdd,0xdd,0xdd);
      break;
    case eColorID_WidgetForeground:
      aColor = NS_RGB(0x00,0x00,0x00);        
      break;
    case eColorID_WidgetSelectBackground:
      aColor = NS_RGB(0x80,0x80,0x80);
      break;
    case eColorID_WidgetSelectForeground:
      aColor = NS_RGB(0x00,0x00,0x80);
      break;
    case eColorID_Widget3DHighlight:
      aColor = NS_RGB(0xa0,0xa0,0xa0);
      break;
    case eColorID_Widget3DShadow:
      aColor = NS_RGB(0x40,0x40,0x40);
      break;
    case eColorID_TextBackground:
      aColor = NS_RGB(0xff,0xff,0xff);
      break;
    case eColorID_TextForeground:
      aColor = NS_RGB(0x00,0x00,0x00);
      break;
    case eColorID_TextSelectBackground:
      aColor = GetColorFromNSColor([NSColor selectedTextBackgroundColor]);
      break;
    case eColorID_highlight: // CSS2 color
      aColor = GetColorFromNSColor([NSColor alternateSelectedControlColor]);
      break;
    case eColorID__moz_menuhover:
      aColor = GetColorFromNSColor([NSColor alternateSelectedControlColor]);
      break;      
    case eColorID_TextSelectForeground:
      GetColor(eColorID_TextSelectBackground, aColor);
      if (aColor == 0x000000)
        aColor = NS_RGB(0xff,0xff,0xff);
      else
        aColor = NS_DONT_CHANGE_COLOR;
      break;
    case eColorID_highlighttext:  // CSS2 color
    case eColorID__moz_menuhovertext:
      aColor = GetColorFromNSColor([NSColor alternateSelectedControlTextColor]);
      break;
    case eColorID_IMESelectedRawTextBackground:
    case eColorID_IMESelectedConvertedTextBackground:
    case eColorID_IMERawInputBackground:
    case eColorID_IMEConvertedTextBackground:
      aColor = NS_TRANSPARENT;
      break;
    case eColorID_IMESelectedRawTextForeground:
    case eColorID_IMESelectedConvertedTextForeground:
    case eColorID_IMERawInputForeground:
    case eColorID_IMEConvertedTextForeground:
      aColor = NS_SAME_AS_FOREGROUND_COLOR;
      break;
    case eColorID_IMERawInputUnderline:
    case eColorID_IMEConvertedTextUnderline:
      aColor = NS_40PERCENT_FOREGROUND_COLOR;
      break;
    case eColorID_IMESelectedRawTextUnderline:
    case eColorID_IMESelectedConvertedTextUnderline:
      aColor = NS_SAME_AS_FOREGROUND_COLOR;
      break;
    case eColorID_SpellCheckerUnderline:
      aColor = NS_RGB(0xff, 0, 0);
      break;

      //
      // css2 system colors http://www.w3.org/TR/REC-CSS2/ui.html#system-colors
      //
      // It's really hard to effectively map these to the Appearance Manager properly,
      // since they are modeled word for word after the win32 system colors and don't have any 
      // real counterparts in the Mac world. I'm sure we'll be tweaking these for 
      // years to come. 
      //
      // Thanks to mpt26@student.canterbury.ac.nz for the hardcoded values that form the defaults
      //  if querying the Appearance Manager fails ;)
      //
    case eColorID__moz_mac_buttonactivetext:
    case eColorID__moz_mac_defaultbuttontext:
      if (nsCocoaFeatures::OnYosemiteOrLater()) {
        aColor = NS_RGB(0xFF,0xFF,0xFF);
        break;
      }
      // Otherwise fall through and return the regular button text:
      
    case eColorID_buttontext:
    case eColorID__moz_buttonhovertext:
      aColor = GetColorFromNSColor([NSColor controlTextColor]);
      break;
    case eColorID_captiontext:
    case eColorID_menutext:
    case eColorID_infotext:
    case eColorID__moz_menubartext:
      aColor = GetColorFromNSColor([NSColor textColor]);
      break;
    case eColorID_windowtext:
      aColor = GetColorFromNSColor([NSColor windowFrameTextColor]);
      break;
    case eColorID_activecaption:
      aColor = GetColorFromNSColor([NSColor gridColor]);
      break;
    case eColorID_activeborder:
      aColor = GetColorFromNSColor([NSColor keyboardFocusIndicatorColor]);
      break;
     case eColorID_appworkspace:
      aColor = NS_RGB(0xFF,0xFF,0xFF);
      break;
    case eColorID_background:
      aColor = NS_RGB(0x63,0x63,0xCE);
      break;
    case eColorID_buttonface:
    case eColorID__moz_buttonhoverface:
      aColor = NS_RGB(0xF0,0xF0,0xF0);
      break;
    case eColorID_buttonhighlight:
      aColor = NS_RGB(0xFF,0xFF,0xFF);
      break;
    case eColorID_buttonshadow:
      aColor = NS_RGB(0xDC,0xDC,0xDC);
      break;
    case eColorID_graytext:
      aColor = GetColorFromNSColor([NSColor disabledControlTextColor]);
      break;
    case eColorID_inactiveborder:
      aColor = GetColorFromNSColor([NSColor controlBackgroundColor]);
      break;
    case eColorID_inactivecaption:
      aColor = GetColorFromNSColor([NSColor controlBackgroundColor]);
      break;
    case eColorID_inactivecaptiontext:
      aColor = NS_RGB(0x45,0x45,0x45);
      break;
    case eColorID_scrollbar:
      aColor = GetColorFromNSColor([NSColor scrollBarColor]);
      break;
    case eColorID_threeddarkshadow:
      aColor = NS_RGB(0xDC,0xDC,0xDC);
      break;
    case eColorID_threedshadow:
      aColor = NS_RGB(0xE0,0xE0,0xE0);
      break;
    case eColorID_threedface:
      aColor = NS_RGB(0xF0,0xF0,0xF0);
      break;
    case eColorID_threedhighlight:
      aColor = GetColorFromNSColor([NSColor highlightColor]);
      break;
    case eColorID_threedlightshadow:
      aColor = NS_RGB(0xDA,0xDA,0xDA);
      break;
    case eColorID_menu:
      aColor = GetColorFromNSColor([NSColor alternateSelectedControlTextColor]);
      break;
    case eColorID_infobackground:
      aColor = NS_RGB(0xFF,0xFF,0xC7);
      break;
    case eColorID_windowframe:
      aColor = GetColorFromNSColor([NSColor gridColor]);
      break;
    case eColorID_window:
    case eColorID__moz_field:
    case eColorID__moz_combobox:
      aColor = NS_RGB(0xff,0xff,0xff);
      break;
    case eColorID__moz_fieldtext:
    case eColorID__moz_comboboxtext:
      aColor = GetColorFromNSColor([NSColor controlTextColor]);
      break;
    case eColorID__moz_dialog:
      aColor = GetColorFromNSColor([NSColor controlHighlightColor]);
      break;
    case eColorID__moz_dialogtext:
    case eColorID__moz_cellhighlighttext:
    case eColorID__moz_html_cellhighlighttext:
      aColor = GetColorFromNSColor([NSColor controlTextColor]);
      break;
    case eColorID__moz_dragtargetzone:
      aColor = GetColorFromNSColor([NSColor selectedControlColor]);
      break;
    case eColorID__moz_mac_chrome_active:
    case eColorID__moz_mac_chrome_inactive: {
      int grey = NativeGreyColorAsInt(toolbarFillGrey, (aID == eColorID__moz_mac_chrome_active));
      aColor = NS_RGB(grey, grey, grey);
    }
      break;
    case eColorID__moz_mac_focusring:
      aColor = GetColorFromNSColorWithAlpha([NSColor keyboardFocusIndicatorColor], 0.48);
      break;
    case eColorID__moz_mac_menushadow:
      aColor = NS_RGB(0xA3,0xA3,0xA3);
      break;          
    case eColorID__moz_mac_menutextdisable:
      aColor = NS_RGB(0x98,0x98,0x98);
      break;      
    case eColorID__moz_mac_menutextselect:
      aColor = GetColorFromNSColor([NSColor selectedMenuItemTextColor]);
      break;      
    case eColorID__moz_mac_disabledtoolbartext:
      aColor = GetColorFromNSColor([NSColor disabledControlTextColor]);
      break;
    case eColorID__moz_mac_menuselect:
      aColor = GetColorFromNSColor([NSColor alternateSelectedControlColor]);
      break;
    case eColorID__moz_buttondefault:
      aColor = NS_RGB(0xDC,0xDC,0xDC);
      break;
    case eColorID__moz_cellhighlight:
    case eColorID__moz_html_cellhighlight:
    case eColorID__moz_mac_secondaryhighlight:
      // For inactive list selection
      aColor = GetColorFromNSColor([NSColor secondarySelectedControlColor]);
      break;
    case eColorID__moz_eventreerow:
      // Background color of even list rows.
      aColor = GetColorFromNSColor([[NSColor controlAlternatingRowBackgroundColors] objectAtIndex:0]);
      break;
    case eColorID__moz_oddtreerow:
      // Background color of odd list rows.
      aColor = GetColorFromNSColor([[NSColor controlAlternatingRowBackgroundColors] objectAtIndex:1]);
      break;
    case eColorID__moz_nativehyperlinktext:
      // There appears to be no available system defined color. HARDCODING to the appropriate color.
      aColor = NS_RGB(0x14,0x4F,0xAE);
      break;
    default:
      NS_WARNING("Someone asked nsILookAndFeel for a color I don't know about");
      aColor = NS_RGB(0xff,0xff,0xff);
      res = NS_ERROR_FAILURE;
      break;
    }
  
  return res;

  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
}

nsresult
nsLookAndFeel::GetIntImpl(IntID aID, int32_t &aResult)
{
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;

  nsresult res = nsXPLookAndFeel::GetIntImpl(aID, aResult);
  if (NS_SUCCEEDED(res))
    return res;
  res = NS_OK;
  
  switch (aID) {
    case eIntID_CaretBlinkTime:
      aResult = 567;
      break;
    case eIntID_CaretWidth:
      aResult = 1;
      break;
    case eIntID_ShowCaretDuringSelection:
      aResult = 0;
      break;
    case eIntID_SelectTextfieldsOnKeyFocus:
      // Select textfield content when focused by kbd
      // used by EventStateManager::sTextfieldSelectModel
      aResult = 1;
      break;
    case eIntID_SubmenuDelay:
      aResult = 200;
      break;
    case eIntID_TooltipDelay:
      aResult = 500;
      break;
    case eIntID_MenusCanOverlapOSBar:
      // xul popups are not allowed to overlap the menubar.
      aResult = 0;
      break;
    case eIntID_SkipNavigatingDisabledMenuItem:
      aResult = 1;
      break;
    case eIntID_DragThresholdX:
    case eIntID_DragThresholdY:
      aResult = 4;
      break;
    case eIntID_ScrollArrowStyle:
      aResult = eScrollArrow_None;
      break;
    case eIntID_ScrollSliderStyle:
      aResult = eScrollThumbStyle_Proportional;
      break;
    case eIntID_UseOverlayScrollbars:
      if (!mUseOverlayScrollbarsCached) {
        mUseOverlayScrollbars = SystemWantsOverlayScrollbars() ? 1 : 0;
        mUseOverlayScrollbarsCached = true;
      }
      aResult = mUseOverlayScrollbars;
      break;
    case eIntID_AllowOverlayScrollbarsOverlap:
      if (!mAllowOverlayScrollbarsOverlapCached) {
        mAllowOverlayScrollbarsOverlap = AllowOverlayScrollbarsOverlap() ? 1 : 0;
        mAllowOverlayScrollbarsOverlapCached = true;
      }
      aResult = mAllowOverlayScrollbarsOverlap;
      break;
    case eIntID_ScrollbarDisplayOnMouseMove:
      aResult = 0;
      break;
    case eIntID_ScrollbarFadeBeginDelay:
      aResult = 450;
      break;
    case eIntID_ScrollbarFadeDuration:
      aResult = 200;
      break;
    case eIntID_TreeOpenDelay:
      aResult = 1000;
      break;
    case eIntID_TreeCloseDelay:
      aResult = 1000;
      break;
    case eIntID_TreeLazyScrollDelay:
      aResult = 150;
      break;
    case eIntID_TreeScrollDelay:
      aResult = 100;
      break;
    case eIntID_TreeScrollLinesMax:
      aResult = 3;
      break;
    case eIntID_DWMCompositor:
    case eIntID_WindowsClassic:
    case eIntID_WindowsDefaultTheme:
    case eIntID_TouchEnabled:
    case eIntID_WindowsThemeIdentifier:
    case eIntID_OperatingSystemVersionIdentifier:
      aResult = 0;
      res = NS_ERROR_NOT_IMPLEMENTED;
      break;
    case eIntID_MacGraphiteTheme:
      aResult = [NSColor currentControlTint] == NSGraphiteControlTint;
      break;
    case eIntID_MacYosemiteTheme:
      aResult = nsCocoaFeatures::OnYosemiteOrLater();
      break;
    case eIntID_AlertNotificationOrigin:
      aResult = NS_ALERT_TOP;
      break;
    case eIntID_TabFocusModel:
      aResult = [NSApp isFullKeyboardAccessEnabled] ?
                  nsIContent::eTabFocus_any : nsIContent::eTabFocus_textControlsMask;
      break;
    case eIntID_ScrollToClick:
    {
      aResult = [[NSUserDefaults standardUserDefaults] boolForKey:@"AppleScrollerPagingBehavior"];
    }
      break;
    case eIntID_ChosenMenuItemsShouldBlink:
      aResult = 1;
      break;
    case eIntID_IMERawInputUnderlineStyle:
    case eIntID_IMEConvertedTextUnderlineStyle:
    case eIntID_IMESelectedRawTextUnderlineStyle:
    case eIntID_IMESelectedConvertedTextUnderline:
      aResult = NS_STYLE_TEXT_DECORATION_STYLE_SOLID;
      break;
    case eIntID_SpellCheckerUnderlineStyle:
      aResult = NS_STYLE_TEXT_DECORATION_STYLE_DOTTED;
      break;
    case eIntID_ScrollbarButtonAutoRepeatBehavior:
      aResult = 0;
      break;
    case eIntID_SwipeAnimationEnabled:
      aResult = 0;
      if ([NSEvent respondsToSelector:@selector(
            isSwipeTrackingFromScrollEventsEnabled)]) {
        aResult = [NSEvent isSwipeTrackingFromScrollEventsEnabled] ? 1 : 0;
      }
      break;
    case eIntID_ColorPickerAvailable:
      aResult = 1;
      break;
    case eIntID_ContextMenuOffsetVertical:
      aResult = -6;
      break;
    case eIntID_ContextMenuOffsetHorizontal:
      aResult = 1;
      break;
    default:
      aResult = 0;
      res = NS_ERROR_FAILURE;
  }
  return res;

  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
}

nsresult
nsLookAndFeel::GetFloatImpl(FloatID aID, float &aResult)
{
  nsresult res = nsXPLookAndFeel::GetFloatImpl(aID, aResult);
  if (NS_SUCCEEDED(res))
    return res;
  res = NS_OK;
  
  switch (aID) {
    case eFloatID_IMEUnderlineRelativeSize:
      aResult = 2.0f;
      break;
    case eFloatID_SpellCheckerUnderlineRelativeSize:
      aResult = 2.0f;
      break;
    default:
      aResult = -1.0;
      res = NS_ERROR_FAILURE;
  }

  return res;
}

bool nsLookAndFeel::UseOverlayScrollbars()
{
  return GetInt(eIntID_UseOverlayScrollbars) != 0;
}

bool nsLookAndFeel::SystemWantsOverlayScrollbars()
{
  return ([NSScroller respondsToSelector:@selector(preferredScrollerStyle)] &&
          [NSScroller preferredScrollerStyle] == mozNSScrollerStyleOverlay);
}

bool nsLookAndFeel::AllowOverlayScrollbarsOverlap()
{
  return (UseOverlayScrollbars());
}

bool
nsLookAndFeel::GetFontImpl(FontID aID, nsString &aFontName,
                           gfxFontStyle &aFontStyle,
                           float aDevPixPerCSSPixel)
{
    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;

    // hack for now
    if (aID == eFont_Window || aID == eFont_Document) {
        aFontStyle.style      = NS_FONT_STYLE_NORMAL;
        aFontStyle.weight     = NS_FONT_WEIGHT_NORMAL;
        aFontStyle.stretch    = NS_FONT_STRETCH_NORMAL;
        aFontStyle.size       = 14 * aDevPixPerCSSPixel;
        aFontStyle.systemFont = true;

        aFontName.AssignLiteral("sans-serif");
        return true;
    }

    gfxPlatformMac::LookupSystemFont(aID, aFontName, aFontStyle,
                                     aDevPixPerCSSPixel);

    return true;

    NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
}

nsTArray<LookAndFeelInt>
nsLookAndFeel::GetIntCacheImpl()
{
  nsTArray<LookAndFeelInt> lookAndFeelIntCache =
    nsXPLookAndFeel::GetIntCacheImpl();

  LookAndFeelInt useOverlayScrollbars;
  useOverlayScrollbars.id = eIntID_UseOverlayScrollbars;
  useOverlayScrollbars.value = GetInt(eIntID_UseOverlayScrollbars);
  lookAndFeelIntCache.AppendElement(useOverlayScrollbars);

  LookAndFeelInt allowOverlayScrollbarsOverlap;
  allowOverlayScrollbarsOverlap.id = eIntID_AllowOverlayScrollbarsOverlap;
  allowOverlayScrollbarsOverlap.value = GetInt(eIntID_AllowOverlayScrollbarsOverlap);
  lookAndFeelIntCache.AppendElement(allowOverlayScrollbarsOverlap);

  return lookAndFeelIntCache;
}

void
nsLookAndFeel::SetIntCacheImpl(const nsTArray<LookAndFeelInt>& aLookAndFeelIntCache)
{
  for (auto entry : aLookAndFeelIntCache) {
    switch(entry.id) {
      case eIntID_UseOverlayScrollbars:
        mUseOverlayScrollbars = entry.value;
        mUseOverlayScrollbarsCached = true;
        break;
      case eIntID_AllowOverlayScrollbarsOverlap:
        mAllowOverlayScrollbarsOverlap = entry.value;
        mAllowOverlayScrollbarsOverlapCached = true;
        break;
    }
  }
}

void
nsLookAndFeel::RefreshImpl()
{
  // We should only clear the cache if we're in the main browser process.
  // Otherwise, we should wait for the parent to inform us of new values
  // to cache via LookAndFeel::SetIntCache.
  if (XRE_IsParentProcess()) {
    mUseOverlayScrollbarsCached = false;
    mAllowOverlayScrollbarsOverlapCached = false;
  }
}