3 files changed, 27 insertions, 8 deletions
diff --git a/dom/performance/PerformanceTiming.cpp b/dom/performance/PerformanceTiming.cpp
index 97bbcb0ca..e2f76a21f 100755
--- a/dom/performance/PerformanceTiming.cpp
+++ b/dom/performance/PerformanceTiming.cpp
@@ -46,6 +46,23 @@ PerformanceTiming::PerformanceTiming(Performance* aPerformance,
     mReportCrossOriginRedirect = mTimingAllowed && redirectsPassCheck;
   }
 
+  mSecureConnection = false;
+  nsCOMPtr<nsIURI> uri;
+  if (aHttpChannel) {
+    aHttpChannel->GetURI(getter_AddRefs(uri));
+  } else {
+    nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aChannel);
+    if (httpChannel) {
+      httpChannel->GetURI(getter_AddRefs(uri));
+    }
+  }
+
+  if (uri) {
+    nsresult rv = uri->SchemeIs("https", &mSecureConnection);
+    if (NS_FAILED(rv)) {
+      mSecureConnection = false;
+    }
+  }
   InitializeTimingInfo(aChannel);
 }
 
@@ -89,7 +106,8 @@ PerformanceTiming::InitializeTimingInfo(nsITimedChannel* aChannel)
         mConnectStart = mAsyncOpen;
       }
 
-      if (!mSecureConnectionStart.IsNull() && mSecureConnectionStart < mAsyncOpen) {
+      if (mSecureConnection && !mSecureConnectionStart.IsNull() &&
+          mSecureConnectionStart < mAsyncOpen) {
         mSecureConnectionStart = mAsyncOpen;
       }
 
@@ -307,12 +325,11 @@ PerformanceTiming::SecureConnectionStartHighRes()
   if (!nsContentUtils::IsPerformanceTimingEnabled() || !IsInitialized()) {
     return mZeroTime;
   }
-
-  // Round down to the nearest 1ms
-  const double maxResolutionMs = 1;
-  return mSecureConnectionStart.IsNull()
-         ? mZeroTime
-         : floor(TimeStampToDOMHighRes(mSecureConnectionStart) / maxResolutionMs) * maxResolutionMs;
+  return !mSecureConnection
+    ? 0 // We use 0 here, because mZeroTime is sometimes set to the navigation
+        // start time.
+    : (mSecureConnectionStart.IsNull() ? mZeroTime
+                                       : TimerClamping::ReduceMsTimeValue(TimeStampToDOMHighRes(mSecureConnectionStart)));
 }
 
 DOMTimeMilliSec
diff --git a/dom/performance/PerformanceTiming.h b/dom/performance/PerformanceTiming.h
index edfac8d02..fc7e7d5bd 100755
--- a/dom/performance/PerformanceTiming.h
+++ b/dom/performance/PerformanceTiming.h
@@ -274,6 +274,8 @@ private:
   // redirectEnd attributes. It is false if there were no redirects, or if
   // any of the responses didn't pass the timing-allow-check
   bool mReportCrossOriginRedirect;
+
+  bool mSecureConnection;
 };
 
 } // namespace dom
diff --git a/dom/performance/tests/test_performance_user_timing.js b/dom/performance/tests/test_performance_user_timing.js
index 3d05ebb77..cd8261bbd 100644
--- a/dom/performance/tests/test_performance_user_timing.js
+++ b/dom/performance/tests/test_performance_user_timing.js
@@ -263,7 +263,7 @@ var steps = [
                 performance.measure("test", n);
                 ok(true, "Measure created from reserved name as starting time: " + n);
             } catch (e) {
-                ok(["redirectStart", "redirectEnd", "unloadEventStart", "unloadEventEnd", "loadEventEnd"].indexOf(n) >= 0,
+                ok(["redirectStart", "redirectEnd", "unloadEventStart", "unloadEventEnd", "loadEventEnd", "secureConnectionStart"].indexOf(n) >= 0,
                    "Measure created from reserved name as starting time: " + n + " and threw expected error");
             }
         };