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

- Bug 1235979 - Remove spammy printf that got left by accident when bug 1226904 landed. r=thinker (fc6fe64f23)
- Bug 1208344 part 1: Make EnsurePhysicalProperty() return the property directly, instead of using in/out-param. r=heycam (9515887dd7)
- Bug 1208344 part 2: Make EnsurePhysicalProperty() (not its callers) check whether property is logical. r=heycam (defa671bab)
- Bug 1208344 part 3: Rename MapSinglePropertyInto() args, to make src-vs-target distinctions clearer. r=heycam (bfd2e2c9bc)
- Bug 1208344 part 4: Make MapSinglePropertyInto() take the source property as an arg (unused for the moment). r=heycam (d1278eb58a)
- Bug 1208344 part 5: Add (preffed-off) support for "-webkit-box-orient" CSS property, as a writing-mode-dependent alias for "flex-direction". r=heycam (d8407990aa)
- Bug 1208344 part 6: Move new CSS_PROPERTY_LOGICAL_CUSTOM flag up with other LOGICAL flags, and adjust bits accordingly. r=heycam (df27d64733)
- Bug 1208344 part 7: Add mochitest to test how "-webkit-box-orient" maps to "flex-direction". r=heycam (c448070877)
- Bug 686225 - Work around buggy AAT fonts for Bengali and Kannada scripts. r=jdaggett (17afddbc6c)
- Bug 739117 - Avoid bidi-wrapping the text to be shaped if Core Text direction override API is available. r=jdaggett (c492390922)
- Bug 1156581 - Add null check to nsSVGEffects::InvalidateRenderingObservers to prevent crashes r=dholbert (4c0460e7ac)
- remove windows accents (8b0ad08f11)
- Bug 1123654 - Replace use of [deprecated] GetStockObject(DEFAULT_GUI_FONT) with newer API; results in use of Tahoma in place of Microsoft Sans Serif in various contexts. r=jmathies (3a81fc1bed)
- put back cleartype for winXP (1c24e5ae09)
- Bug 1240180 - Optimize native theme scaling for the single-monitor case. r=emk (a5846457ab)
- Bug 1242720 - Use (non-dynamic) resolution from GetDeviceCaps when dealing with native-theme code that does not handle dynamic changes to system DPI. r=emk (7c25841f0b)
- More win accent removal (afd6af9fd2)
- some more vista or later stuff (1d99554064)
- missing bits of Bug 1243720 - Send accessibility theme state down to the content process on Windows. r=jimm (8f00b4f3ca)
- Bug 1153460 - Support new Fitzpatrick emoji modifiers and regional symbol indicators in Apple Color Emoji font. r=jdaggett (6faf5f30e6)
- Bug 1230497 - Ignore font fallback in Core Text shaping if it's just for a join-control character. r=jdaggett (b612806a42)
- Bug 1153460 - Followup to fix warnings-as-errors build failure on a CLOSED TREE. r=bustage. (12d492772c)
- bug 1243077 - make it possible to get MaiAtkObject::mAccWrap from an AtkObject* without casting to Accessible* or ProxyAccessible* r=davidb (d8f690b6cd)
- Bug 1238403 - Fix inconsistent indenting in layout/style/. r=xidorn (4f24334234)
- Bug 717722 - Implement WebKitCSSMatrix. r=baku (c10f90ff6e)
- Bug 1241723. Update WebKitCSSMatrix.idl to match latest spec updates. r=baku (5f8c33ff14)
- Bug 1241727 - Inverting non-invertible WebKitCSSMatrix should throw NotSupportedError. r=baku (c7791802b8)
- Bug 1241575 - Use transform property syntax to parse WebKitCSSMatrix transform list. r=heycam (5f886e2bd9)
- bug 1243077 - add AccessibleOrProxy::ChildCount() r=davidb (044537f53c)
- bug 1243077 - add AccessibleOrProxy::Role() r=davidb (3f61d03c8e)
- bug 1243077 - add AccessibleOrProxy::ChildAt() r=davidb (91288f269f)
- bug 1243077 - add AccessibleOrProxy::FirstChild() r=davidb (ea3f984716)
- bug 1243077 - add AccessibleOrProxy::LastChild() r=davidb (2181f1740b)
- Bug 1237720: Put "-webkit-min-device-pixel-ratio"/"-webkit-max-device-pixel-ratio" behind its own disabled pref. r=heycam (9f75535617)
- Bug 1239153: Accept unitless '0' for angle values in CSS -webkit-linear-gradient() expressions. r=heycam (c11657a6c9)
- Bug 1239799 part 1: Make check for -webkit-device-pixel-ratio pref more targeted, so we can support other webkit-prefixed media queries. r=heycam (1e8a40127e)
- Bug 1239799 part 2: Add support for @media(-webkit-transform-3d) media query, for web compatibility. r=heycam (f7ff08423e)
- guard some code for 10.5/10.6 which didn't get run, but coulnd't natively compile (cf68e969fd)
- Bug 1019856 - avoid double-buffering in BasicCompositor when window allows it. r=mattwoodrow (e94cfc3fb4)

gfx/layers/basic/BasicCompositor.cpp

@@ -152,6 +152,32 @@ BasicCompositor::CreateRenderTargetFromSource(const IntRect &aRect,
   return nullptr;
 }
 
+already_AddRefed<CompositingRenderTarget>
+BasicCompositor::CreateRenderTargetForWindow(const IntRect& aRect, SurfaceInitMode aInit, BufferMode aBufferMode)
+{
+  if (aBufferMode != BufferMode::BUFFER_NONE) {
+    return CreateRenderTarget(aRect, aInit);
+  }
+
+  MOZ_ASSERT(aRect.width != 0 && aRect.height != 0, "Trying to create a render target of invalid size");
+
+  if (aRect.width * aRect.height == 0) {
+    return nullptr;
+  }
+
+  MOZ_ASSERT(mDrawTarget);
+
+  // Adjust bounds rect to account for new origin at (0, 0).
+  IntRect rect(0, 0, aRect.XMost(), aRect.YMost());
+  RefPtr<BasicCompositingRenderTarget> rt = new BasicCompositingRenderTarget(mDrawTarget, rect);
+
+  if (aInit == INIT_MODE_CLEAR) {
+    mDrawTarget->ClearRect(gfx::Rect(aRect));
+  }
+
+  return rt.forget();
+}
+
 already_AddRefed<DataTextureSource>
 BasicCompositor::CreateDataTextureSource(TextureFlags aFlags)
 {
@@ -542,13 +568,14 @@ BasicCompositor::BeginFrame(const nsIntRegion& aInvalidRegion,
     *aRenderBoundsOut = Rect();
   }
 
+  BufferMode bufferMode = BufferMode::BUFFERED;
   if (mTarget) {
     // If we have a copy target, then we don't have a widget-provided mDrawTarget (currently). Use a dummy
     // placeholder so that CreateRenderTarget() works.
     mDrawTarget = gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget();
   } else {
     // StartRemoteDrawingInRegion can mutate mInvalidRegion.
-    mDrawTarget = mWidget->StartRemoteDrawingInRegion(mInvalidRegion);
+    mDrawTarget = mWidget->StartRemoteDrawingInRegion(mInvalidRegion, &bufferMode);
     if (!mDrawTarget) {
       return;
     }
@@ -566,7 +593,7 @@ BasicCompositor::BeginFrame(const nsIntRegion& aInvalidRegion,
   // Setup an intermediate render target to buffer all compositing. We will
   // copy this into mDrawTarget (the widget), and/or mTarget in EndFrame()
   RefPtr<CompositingRenderTarget> target =
-    CreateRenderTarget(mInvalidRect.ToUnknownRect(), INIT_MODE_CLEAR);
+    CreateRenderTargetForWindow(mInvalidRect.ToUnknownRect(), INIT_MODE_CLEAR, bufferMode);
   if (!target) {
     if (!mTarget) {
       mWidget->EndRemoteDrawingInRegion(mDrawTarget, mInvalidRegion);
@@ -577,8 +604,7 @@ BasicCompositor::BeginFrame(const nsIntRegion& aInvalidRegion,
 
   // We only allocate a surface sized to the invalidated region, so we need to
   // translate future coordinates.
-  mRenderTarget->mDrawTarget->SetTransform(Matrix::Translation(-mInvalidRect.x,
-                                                               -mInvalidRect.y));
+  mRenderTarget->mDrawTarget->SetTransform(Matrix::Translation(-mRenderTarget->GetOrigin()));
 
   gfxUtils::ClipToRegion(mRenderTarget->mDrawTarget,
                          mInvalidRegion.ToUnknownRegion());
@@ -616,22 +642,25 @@ BasicCompositor::EndFrame()
   // Pop aInvalidregion
   mRenderTarget->mDrawTarget->PopClip();
 
-  // Note: Most platforms require us to buffer drawing to the widget surface.
-  // That's why we don't draw to mDrawTarget directly.
-  RefPtr<SourceSurface> source = mRenderTarget->mDrawTarget->Snapshot();
-  RefPtr<DrawTarget> dest(mTarget ? mTarget : mDrawTarget);
+  if (mTarget || mRenderTarget->mDrawTarget != mDrawTarget) {
+    // Note: Most platforms require us to buffer drawing to the widget surface.
+    // That's why we don't draw to mDrawTarget directly.
+    RefPtr<SourceSurface> source = mRenderTarget->mDrawTarget->Snapshot();
+    RefPtr<DrawTarget> dest(mTarget ? mTarget : mDrawTarget);
 
-  nsIntPoint offset = mTarget ? mTargetBounds.TopLeft() : nsIntPoint();
+    nsIntPoint offset = mTarget ? mTargetBounds.TopLeft() : nsIntPoint();
 
-  // The source DrawTarget is clipped to the invalidation region, so we have
-  // to copy the individual rectangles in the region or else we'll draw blank
-  // pixels.
-  for (auto iter = mInvalidRegion.RectIter(); !iter.Done(); iter.Next()) {
-    const LayoutDeviceIntRect& r = iter.Get();
-    dest->CopySurface(source,
-                      IntRect(r.x - mInvalidRect.x, r.y - mInvalidRect.y, r.width, r.height),
-                      IntPoint(r.x - offset.x, r.y - offset.y));
+    // The source DrawTarget is clipped to the invalidation region, so we have
+    // to copy the individual rectangles in the region or else we'll draw blank
+    // pixels.
+    for (auto iter = mInvalidRegion.RectIter(); !iter.Done(); iter.Next()) {
+      const LayoutDeviceIntRect& r = iter.Get();
+      dest->CopySurface(source,
+                        IntRect(r.x, r.y, r.width, r.height) - mRenderTarget->GetOrigin(),
+                        IntPoint(r.x, r.y) - offset);
+    }
   }
+
   if (!mTarget) {
     mWidget->EndRemoteDrawingInRegion(mDrawTarget, mInvalidRegion);
   }