Bug 1276824 (part 2) - Fix up checks for calls to gfxContext::Create{,PreservingTransform}OrNull(). r=milan.

--HG--
extra : rebase_source : 80644c1a6658da553c13ae1ab3b8d03e916ee6e7

dom/canvas/CanvasRenderingContext2D.cpp

@@ -3604,6 +3604,8 @@ struct MOZ_STACK_CLASS CanvasBidiProcessor : public nsBidiPresUtils::BidiProcess
     // not render well via the code below.
     if (mOp == CanvasRenderingContext2D::TextDrawOperation::FILL &&
         mState->StyleIsColor(CanvasRenderingContext2D::Style::FILL)) {
+      // TODO: determine if mCtx->mTarget is guaranteed to be non-null and valid
+      // here. If it's not, thebes will be null and we'll crash.
       RefPtr<gfxContext> thebes =
         gfxContext::CreatePreservingTransformOrNull(mCtx->mTarget);
       nscolor fill = mState->colorStyles[CanvasRenderingContext2D::Style::FILL];
@@ -4992,7 +4994,8 @@ CanvasRenderingContext2D::DrawWindow(nsGlobalWindow& aWindow, double aX,
       UsedOperation() == CompositionOp::OP_OVER)
   {
     thebes = gfxContext::CreateOrNull(mTarget);
-    MOZ_ASSERT(thebes); // alrady checked the draw target above
+    MOZ_ASSERT(thebes); // already checked the draw target above
+                        // (in SupportsAzureContentForDrawTarget)
     thebes->SetMatrix(gfxMatrix(matrix._11, matrix._12, matrix._21,
                                 matrix._22, matrix._31, matrix._32));
   } else {

gfx/layers/basic/BasicLayerManager.cpp

@@ -932,8 +932,6 @@ BasicLayerManager::PaintLayer(gfxContext* aTarget,
 
     // Temporary fast fix for bug 725886
     // Revert these changes when 725886 is ready
-    MOZ_ASSERT(untransformedDT && untransformedDT->IsValid(),
-               "We should always allocate an untransformed surface with 3d transforms!");
 #ifdef DEBUG
     if (aLayer->GetDebugColorIndex() != 0) {
       Color color((aLayer->GetDebugColorIndex() & 1) ? 1.f : 0.f,

gfx/tests/gtest/gfxFontSelectionTest.cpp

@@ -193,6 +193,9 @@ MakeContext ()
         CreateOffscreenContentDrawTarget(IntSize(size, size),
                                          SurfaceFormat::B8G8R8X8);
     RefPtr<gfxContext> ctx = gfxContext::CreateOrNull(drawTarget);
+    if (!ctx) {
+        MOZ_CRASH("gfxContext creation failed");
+    }
 
     return ctx.forget();
 }

gfx/tests/gtest/gfxTextRunPerfTest.cpp

@@ -44,6 +44,9 @@ MakeContext ()
         CreateOffscreenContentDrawTarget(IntSize(size, size),
                                          SurfaceFormat::B8G8R8X8);
     RefPtr<gfxContext> ctx = gfxContext::CreateOrNull(drawTarget);
+    if (!ctx) {
+        MOZ_CRASH("gfxContext creation failed");
+    }
 
     return ctx.forget();
 }

gfx/thebes/gfxPlatform.cpp

@@ -1238,7 +1238,7 @@ gfxPlatform::PopulateScreenInfo()
 bool
 gfxPlatform::SupportsAzureContentForDrawTarget(DrawTarget* aTarget)
 {
-  if (!aTarget) {
+  if (!aTarget || !aTarget->IsValid()) {
     return false;
   }
 

layout/base/nsDisplayList.cpp

@@ -565,10 +565,11 @@ GenerateAndPushTextMask(nsIFrame* aFrame, nsRenderingContext* aContext,
   RefPtr<DrawTarget> maskDT =
     sourceTarget->CreateSimilarDrawTarget(drawRect.Size(),
                                           SurfaceFormat::A8);
-  if (!maskDT) {
-    NS_ABORT_OOM(drawRect.width * drawRect.height);
+  if (!maskDT || !maskDT->IsValid()) {
+    return false;
   }
   RefPtr<gfxContext> maskCtx = gfxContext::CreatePreservingTransformOrNull(maskDT);
+  MOZ_ASSERT(maskCtx);
   gfxMatrix currentMatrix = sourceCtx->CurrentMatrix();
   maskCtx->SetMatrix(gfxMatrix::Translation(bounds.TopLeft()) *
                      currentMatrix *

layout/svg/nsSVGIntegrationUtils.cpp

@@ -455,8 +455,12 @@ GenerateMaskSurface(const nsSVGIntegrationUtils::PaintFramesParams& aParams,
                                 SurfaceFormat::A8)
     : ctx.GetDrawTarget()->CreateSimilarDrawTarget(maskSurfaceRect.Size(),
                                                    SurfaceFormat::A8);
+  if (!maskDT || !maskDT->IsValid()) {
+    return;
+  }
 
   RefPtr<gfxContext> maskContext = gfxContext::CreateOrNull(maskDT);
+  MOZ_ASSERT(maskContext);
 
   // Set ctx's matrix on maskContext, offset by the maskSurfaceRect's position.
   // This makes sure that we combine the masks in device space.

widget/cocoa/nsCocoaUtils.mm

@@ -481,16 +481,13 @@ nsresult nsCocoaUtils::CreateNSImageFromImageContainer(imgIContainer *aImage, ui
 
     RefPtr<DrawTarget> drawTarget = gfxPlatform::GetPlatform()->
       CreateOffscreenContentDrawTarget(scaledSize, SurfaceFormat::B8G8R8A8);
-    if (!drawTarget) {
-      NS_ERROR("Failed to create DrawTarget");
+    if (!drawTarget || !drawTarget->IsValid()) {
+      NS_ERROR("Failed to create valid DrawTarget");
       return NS_ERROR_FAILURE;
     }
 
     RefPtr<gfxContext> context = gfxContext::CreateOrNull(drawTarget);
-    if (!context) {
-      NS_ERROR("Failed to create gfxContext");
-      return NS_ERROR_FAILURE;
-    }
+    MOZ_ASSERT(context);
 
     mozilla::image::DrawResult res =
       aImage->Draw(context, scaledSize, ImageRegion::Create(scaledSize),