1 files changed, 17 insertions, 4 deletions
diff --git a/layout/style/StyleComplexColor.h b/layout/style/StyleComplexColor.h
index 4acf90a56..6385b57a1 100644
--- a/layout/style/StyleComplexColor.h
+++ b/layout/style/StyleComplexColor.h
@@ -24,16 +24,29 @@ struct StyleComplexColor
 {
   nscolor mColor;
   uint8_t mForegroundRatio;
-
-  static StyleComplexColor FromColor(nscolor aColor) { return {aColor, 0}; }
-  static StyleComplexColor CurrentColor() { return {NS_RGBA(0, 0, 0, 0), 255}; }
+  // Whether the complex color represents a computed-value time auto
+  // value. This is only a flag indicating that this value should not
+  // be interpolatable with other colors, while other fields still
+  // represents the actual used color of this value.
+  bool mIsAuto;
+
+  static StyleComplexColor FromColor(nscolor aColor) { 
+    return {aColor, 0, false}; 
+  }
+  static StyleComplexColor CurrentColor() { 
+    return {NS_RGBA(0, 0, 0, 0), 255, false}; 
+  }
+  static StyleComplexColor Auto() {
+    return {NS_RGBA(0, 0, 0, 0), 255, true};
+  }
 
   bool IsNumericColor() const { return mForegroundRatio == 0; }
   bool IsCurrentColor() const { return mForegroundRatio == 255; }
 
   bool operator==(const StyleComplexColor& aOther) const {
     return mForegroundRatio == aOther.mForegroundRatio &&
-           (IsCurrentColor() || mColor == aOther.mColor);
+           (IsCurrentColor() || mColor == aOther.mColor) &&
+           mIsAuto == aOther.mIsAuto;
   }
   bool operator!=(const StyleComplexColor& aOther) const {
     return !(*this == aOther);