From f03dccadb31d421b18cce5a7a703f96238bf2e04 Mon Sep 17 00:00:00 2001
From: Heilig Benedek <benecene@gmail.com>
Date: Thu, 13 Apr 2017 01:30:46 +0200
Subject: [PATCH] use white gutter color and paint damage rects over when paint
 starts in software osr

---
 atom/browser/osr/osr_output_device.cc         | 21 +++++++++++++++++--
 .../osr/osr_render_widget_host_view.cc        |  2 +-
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/atom/browser/osr/osr_output_device.cc b/atom/browser/osr/osr_output_device.cc
index 49c4191e21e..d418634272d 100644
--- a/atom/browser/osr/osr_output_device.cc
+++ b/atom/browser/osr/osr_output_device.cc
@@ -4,7 +4,9 @@
 
 #include "atom/browser/osr/osr_output_device.h"
 
+#include "third_party/skia/src/core/SkColor.h"
 #include "third_party/skia/src/core/SkDevice.h"
+#include "third_party/skia/src/core/SkRect.h"
 #include "ui/gfx/skia_util.h"
 
 namespace atom {
@@ -36,8 +38,11 @@ void OffScreenOutputDevice::Resize(
     return;
   }
 
-  if (transparent_)
-    bitmap_->eraseARGB(0, 0, 0, 0);
+  if (transparent_) {
+    bitmap_->eraseColor(SK_ColorTRANSPARENT);
+  } else {
+    bitmap_->eraseColor(SK_ColorWHITE);
+  }
 
   canvas_.reset(new SkCanvas(*bitmap_));
 }
@@ -47,6 +52,18 @@ SkCanvas* OffScreenOutputDevice::BeginPaint(const gfx::Rect& damage_rect) {
   DCHECK(bitmap_.get());
 
   damage_rect_ = damage_rect;
+  SkIRect damage = SkIRect::MakeXYWH(
+    damage_rect_.x(), 
+    damage_rect_.y(), 
+    damage_rect_.width(), 
+    damage_rect_.height()
+  );
+  
+  if (transparent_) {
+    bitmap_->erase(SK_ColorTRANSPARENT, damage);
+  } else {
+    bitmap_->erase(SK_ColorWHITE, damage);
+  }
 
   return canvas_.get();
 }
diff --git a/atom/browser/osr/osr_render_widget_host_view.cc b/atom/browser/osr/osr_render_widget_host_view.cc
index a4faa1b6a7e..3d3729d1ebf 100644
--- a/atom/browser/osr/osr_render_widget_host_view.cc
+++ b/atom/browser/osr/osr_render_widget_host_view.cc
@@ -722,7 +722,7 @@ SkColor OffScreenRenderWidgetHostView::DelegatedFrameHostGetGutterColor(
     SkColor color) const {
   if (render_widget_host_->delegate() &&
       render_widget_host_->delegate()->IsFullscreenForCurrentTab()) {
-    return SK_ColorBLACK;
+    return SK_ColorWHITE;
   }
   return color;
 }