From 9269f6c8a48ea7c17b8338dafd401db606f31da2 Mon Sep 17 00:00:00 2001
From: Ryan Hunt <rhunt@eqrion.net>
Date: Wed, 20 Sep 2017 12:23:01 -0500
Subject: [PATCH] Bug 1401638 - Set and reset mPermitSubpixelAA in push and pop
 layer for DrawTargetCapture. r=bas

MozReview-Commit-ID: DxeNaiAYJvb

--HG--
extra : rebase_source : ea799e4f4d48b52702423d726304b1a5a96fbb65
---
 gfx/2d/DrawTargetCapture.cpp | 11 +++++++++++
 gfx/2d/DrawTargetCapture.h   |  8 ++++++++
 2 files changed, 19 insertions(+)

diff --git a/gfx/2d/DrawTargetCapture.cpp b/gfx/2d/DrawTargetCapture.cpp
index 813252517e3a..87630f15d84a 100644
--- a/gfx/2d/DrawTargetCapture.cpp
+++ b/gfx/2d/DrawTargetCapture.cpp
@@ -227,6 +227,13 @@ DrawTargetCaptureImpl::PushLayer(bool aOpaque,
                                  const IntRect& aBounds,
                                  bool aCopyBackground)
 {
+  // Have to update mPermitSubpixelAA for this DT
+  // because some code paths query the current setting
+  // to determine subpixel AA eligibility.
+  PushedLayer layer(GetPermitSubpixelAA());
+  mPushedLayers.push_back(layer);
+  DrawTarget::SetPermitSubpixelAA(aOpaque);
+
   AppendCommand(PushLayerCommand)(aOpaque,
                                   aOpacity,
                                   aMask,
@@ -238,6 +245,10 @@ DrawTargetCaptureImpl::PushLayer(bool aOpaque,
 void
 DrawTargetCaptureImpl::PopLayer()
 {
+  MOZ_ASSERT(mPushedLayers.size());
+  DrawTarget::SetPermitSubpixelAA(mPushedLayers.back().mOldPermitSubpixelAA);
+  mPushedLayers.pop_back();
+
   AppendCommand(PopLayerCommand)();
 }
 
diff --git a/gfx/2d/DrawTargetCapture.h b/gfx/2d/DrawTargetCapture.h
index 4f53eaa859c3..02fad72cf032 100644
--- a/gfx/2d/DrawTargetCapture.h
+++ b/gfx/2d/DrawTargetCapture.h
@@ -168,6 +168,14 @@ private:
   RefPtr<DrawTarget> mRefDT;
   IntSize mSize;
 
+  struct PushedLayer
+  {
+    PushedLayer(bool aOldPermitSubpixelAA)
+      : mOldPermitSubpixelAA(aOldPermitSubpixelAA)
+    {}
+    bool mOldPermitSubpixelAA;
+  };
+  std::vector<PushedLayer> mPushedLayers;
   std::vector<uint8_t> mDrawCommandStorage;
 };