Bug 773500 Part 1:Store z-component of transform-origin as 0 rather than null when it is omitted. r=dbaron

layout/style/nsCSSParser.cpp

@@ -8362,7 +8362,7 @@ bool CSSParserImpl::ParseTransformOrigin(bool aPerspective)
       nsCSSValue depth;
       if (!ParseVariant(depth, VARIANT_LENGTH | VARIANT_CALC, nsnull) ||
           !nsLayoutUtils::Are3DTransformsEnabled()) {
-        depth.Reset();
+        depth.SetFloatValue(0.0f, eCSSUnit_Pixel);
       }
       value.SetTripletValue(position.mXValue, position.mYValue, depth);
     }

layout/style/nsCSSValue.cpp

@@ -423,10 +423,10 @@ void nsCSSValue::SetPairValue(const nsCSSValue& xValue,
 void nsCSSValue::SetTripletValue(const nsCSSValueTriplet* aValue)
 {
     // triplet should not be used for null/inherit/initial values
-    // Only allow Null for the z component
     NS_ABORT_IF_FALSE(aValue &&
                       aValue->mXValue.GetUnit() != eCSSUnit_Null &&
                       aValue->mYValue.GetUnit() != eCSSUnit_Null &&
+                      aValue->mZValue.GetUnit() != eCSSUnit_Null &&
                       aValue->mXValue.GetUnit() != eCSSUnit_Inherit &&
                       aValue->mYValue.GetUnit() != eCSSUnit_Inherit &&
                       aValue->mZValue.GetUnit() != eCSSUnit_Inherit &&

layout/style/nsStyleAnimation.cpp

@@ -1781,13 +1781,6 @@ nsStyleAnimation::AddWeighted(nsCSSProperty aProperty,
       nsCSSValueTriplet triplet1(*aValue1.GetCSSValueTripletValue());
       nsCSSValueTriplet triplet2(*aValue2.GetCSSValueTripletValue());
 
-      if (triplet1.mZValue.GetUnit() == eCSSUnit_Null) {
-        triplet1.mZValue.SetFloatValue(0.0, eCSSUnit_Pixel);
-      }
-      if (triplet2.mZValue.GetUnit() == eCSSUnit_Null) {
-          triplet2.mZValue.SetFloatValue(0.0, eCSSUnit_Pixel);
-      }
-
       nsCSSUnit unit[3];
       unit[0] = GetCommonUnit(aProperty, triplet1.mXValue.GetUnit(),
                               triplet2.mXValue.GetUnit());
@@ -1816,11 +1809,6 @@ nsStyleAnimation::AddWeighted(nsCSSProperty aProperty,
         }
       }
 
-      if (result->mZValue.GetUnit() == eCSSUnit_Pixel &&
-          result->mZValue.GetFloatValue() == 0.0f) {
-        result->mZValue.Reset();
-      }
-
       aResultValue.SetAndAdoptCSSValueTripletValue(result.forget(),
                                                    eUnit_CSSValueTriplet);
       return true;
@@ -2673,10 +2661,6 @@ nsStyleAnimation::ExtractComputedValue(nsCSSProperty aProperty,
                                     triplet->mZValue)) {
             return false;
           }
-          if (triplet->mZValue.GetUnit() == eCSSUnit_Pixel &&
-              triplet->mZValue.GetFloatValue() == 0.0f) {
-            triplet->mZValue.Reset();
-          }
           aComputedValue.SetAndAdoptCSSValueTripletValue(triplet.forget(),
                                                          eUnit_CSSValueTriplet);
           break;