import changes from `dev' branch of rmottola/Arctic-Fox:

- Bug 1196462 - Add a pref to highlight checkerboarded areas for debugging. r=kats (ffd1d24515)
- Bug 1207944 (part 1) - Pass a gfx::Color& instead of a gfxRGBA& to SetDeviceColor(). r=jwatt. (117317c610)
- Bug 1207944 (part 2) - Pass a gfx::Color& instead of a gfxRGBA& to GetDeviceColor(). r=jwatt. (82739fb35a)
- Bug 1207944 (part 3) - Add a gfxContext::SetColor method that takes a gfx::Color&. r=jwatt. (65d081203d)
- Bug 1207944 (part 4) - Use SetColor(const Color&) when setting from an nscolor. r=jwatt. (4e3ca8e36b)
- Bug 1207944 (part 5) - Use SetColor(const Color&) when setting from a constructed gfxRGBA. r=jwatt. (d4583dbee1)
- Bug 1207944 (part 6) - Use gfx::Color instead of gfxRGBA in ColorStop. r=jwatt. (74ad3407a2)
- Bug 1207944 (part 7) - Use gfx::Color instead of gfxRGBA in BlurCache. r=jwatt. (1402a3f334)
- Bug 1207944 (part 8) - Change nsDisplayBackgroundColor::mColor from gfxRGBA to gfx::Color. r=jwatt. (42259ef66b)
- Bug 1207944 (part 9) - Remove SetColor(const gfxRGBA&). r=jwatt. (064879c237)
- Bug 1208283 (part 1) - Change gfxPattern's single-arg constructor to take a gfx::Color& instead of a gfxRGBA&. r=jwatt. (1aa348d966)
- Bug 1208283 (part 2) - Change ColorLayer::mColor, ColorLayerProperties::mColor, ReadbackLayer::mBackgroundColor from gfxRBGA to gfx::Color. r=jwatt. (859d5c4a45)
- Bug 1208283 (part 3) - Remove the ToDeviceColor() that takes a gfxRGBA. r=jwatt. (525cd78338)
- Bug 1208283 (part 4) - Change FrameMetrics::mBackgroundColor from gfxRGBA to gfx::Color. r=jwatt. (49e3c39013)
- Bug 1208283 (part 5) - Pass a gfx::Color instead of a gfxRGBA to PaintRectToSurface(). r=jwatt. (04997ce877)
- Bug 1157669 - Assert aGroupTarget is not null in PaintSelfOrChildren method. r=nical (7f3cc9c792)
- Bug 1208300 (part 4) - Remove gfxRGBA and some related things. r=jwatt. (c158d04b63)
- Bug 1207931 - Remove no-longer-needed SetBackgroundColor IPC message. r=mattwoodrow. (a54d91bf53)
- Bug 1206904 - Work around APZ crashes when dealing with nested content processes. r=botond (3252333fb4)
- Bug 1189611 - Improve the APZ minimap position and ignore trivial APZ. r=kats (12c5ff5215)
- Bug 1196412 - Correctly scale canvas layers that have a transform applied to fill the screen, r=vlad (5036fd706c)
- Bug 1189473 - Don't paint the tiles in the APZ minimap. r=mstange (fc3db414f7)
- Bug 1189924 - Add a background color to the APZ minimap. r=kats (dd347db883)
- add some dead stuff back in (de8fe1d1a0)
- Treat mix-blend-mode layers as transparent for occlusion culling. (bug 1207041, r=mstange) (c3c3844d7b)

gfx/layers/basic/BasicLayerManager.cpp

@@ -17,7 +17,6 @@
 #include "basic/BasicImplData.h"        // for BasicImplData
 #include "basic/BasicLayers.h"          // for BasicLayerManager, etc
 #include "gfxASurface.h"                // for gfxASurface, etc
-#include "gfxColor.h"                   // for gfxRGBA
 #include "gfxContext.h"                 // for gfxContext, etc
 #include "gfxImageSurface.h"            // for gfxImageSurface
 #include "gfxMatrix.h"                  // for gfxMatrix
@@ -584,7 +583,7 @@ BasicLayerManager::FlashWidgetUpdateArea(gfxContext *aContext)
     float r = float(rand()) / RAND_MAX;
     float g = float(rand()) / RAND_MAX;
     float b = float(rand()) / RAND_MAX;
-    aContext->SetColor(gfxRGBA(r, g, b, 0.2));
+    aContext->SetColor(Color(r, g, b, 0.2f));
     aContext->Paint();
   }
 }
@@ -791,6 +790,7 @@ void
 BasicLayerManager::PaintSelfOrChildren(PaintLayerContext& aPaintContext,
                                        gfxContext* aGroupTarget)
 {
+  MOZ_ASSERT(aGroupTarget);
   BasicImplData* data = ToData(aPaintContext.mLayer);
 
   /* Only paint ourself, or our children - This optimization relies on this! */
@@ -893,6 +893,8 @@ BasicLayerManager::PaintLayer(gfxContext* aTarget,
                               DrawPaintedLayerCallback aCallback,
                               void* aCallbackData)
 {
+  MOZ_ASSERT(aTarget);
+
   PROFILER_LABEL("BasicLayerManager", "PaintLayer",
     js::ProfileEntry::Category::GRAPHICS);
 
@@ -959,7 +961,7 @@ BasicLayerManager::PaintLayer(gfxContext* aTarget,
     paintLayerContext.AnnotateOpaqueRect();
   }
 
-  bool clipIsEmpty = !aTarget || aTarget->GetClipExtents().IsEmpty();
+  bool clipIsEmpty = aTarget->GetClipExtents().IsEmpty();
   if (clipIsEmpty) {
     PaintSelfOrChildren(paintLayerContext, aTarget);
     return;
@@ -1001,10 +1003,9 @@ BasicLayerManager::PaintLayer(gfxContext* aTarget,
     gfxRect destRect;
 #ifdef DEBUG
     if (aLayer->GetDebugColorIndex() != 0) {
-      gfxRGBA  color((aLayer->GetDebugColorIndex() & 1) ? 1.0 : 0.0,
-                     (aLayer->GetDebugColorIndex() & 2) ? 1.0 : 0.0,
-                     (aLayer->GetDebugColorIndex() & 4) ? 1.0 : 0.0,
-                     1.0);
+      Color color((aLayer->GetDebugColorIndex() & 1) ? 1.f : 0.f,
+                  (aLayer->GetDebugColorIndex() & 2) ? 1.f : 0.f,
+                  (aLayer->GetDebugColorIndex() & 4) ? 1.f : 0.f);
 
       nsRefPtr<gfxContext> temp = new gfxContext(untransformedDT, Point(bounds.x, bounds.y));
       temp->SetColor(color);