Bug 1368551 - Remove unneccessary overload of PushStackingContext. r=pchang

This overload is only called in one place, so we can just inline it. It
makes the API a little simpler.

MozReview-Commit-ID: H55IUduUSiJ

gfx/layers/wr/StackingContextHelper.cpp

@@ -26,9 +26,8 @@ StackingContextHelper::StackingContextHelper(const StackingContextHelper& aParen
   WrRect scBounds = aParentSC.ToRelativeWrRect(aLayer->BoundsForStackingContext());
   Layer* layer = aLayer->GetLayer();
   mTransform = aTransform.valueOr(layer->GetTransform());
-  mBuilder->PushStackingContext(scBounds,
-                                1.0f,
-                                mTransform,
+  float opacity = 1.0f;
+  mBuilder->PushStackingContext(scBounds, 0, &opacity, &mTransform,
                                 wr::ToWrMixBlendMode(layer->GetMixBlendMode()));
   mOrigin = aLayer->Bounds().TopLeft();
 }

gfx/webrender_bindings/WebRenderAPI.cpp

@@ -569,16 +569,6 @@ DisplayListBuilder::PushStackingContext(const WrRect& aBounds,
                               maybeTransform, aMixBlendMode);
 }
 
-void
-DisplayListBuilder::PushStackingContext(const WrRect& aBounds,
-                                        const float aOpacity,
-                                        const gfx::Matrix4x4& aTransform,
-                                        const WrMixBlendMode& aMixBlendMode)
-{
-  PushStackingContext(aBounds, 0, &aOpacity,
-                      &aTransform, aMixBlendMode);
-}
-
 void
 DisplayListBuilder::PopStackingContext()
 {

gfx/webrender_bindings/WebRenderAPI.h

@@ -144,11 +144,6 @@ public:
   void Finalize(WrSize& aOutContentSize,
                 wr::BuiltDisplayList& aOutDisplayList);
 
-  void PushStackingContext(const WrRect& aBounds, // TODO: We should work with strongly typed rects
-                           const float aOpacity,
-                           const gfx::Matrix4x4& aTransform,
-                           const WrMixBlendMode& aMixBlendMode);
-
   void PushStackingContext(const WrRect& aBounds, // TODO: We should work with strongly typed rects
                            const uint64_t& aAnimationId,
                            const float* aOpacity,