cef/patch/patches/browser_1161.patch

diff --git compositor/io_surface_layer_mac.mm compositor/io_surface_layer_mac.mm
index 357c65e..371e3c4 100644
--- compositor/io_surface_layer_mac.mm
+++ compositor/io_surface_layer_mac.mm
@@ -295,7 +295,7 @@ void IOSurfaceLayerHelper::EndPumpingFrames() {
   TRACE_EVENT0("browser", "IOSurfaceLayer::drawInCGLContext");
 
   if (!iosurface_->HasIOSurface() || context_->cgl_context() != glContext) {
-    glClearColor(1, 1, 1, 1);
+    glClearColor(0, 0, 0, 0);
     glClear(GL_COLOR_BUFFER_BIT);
     return;
   }
diff --git renderer_host/compositing_iosurface_mac.mm renderer_host/compositing_iosurface_mac.mm
index ba67fc9..2c6a410 100644
--- renderer_host/compositing_iosurface_mac.mm
+++ renderer_host/compositing_iosurface_mac.mm
@@ -168,7 +168,7 @@ bool CompositingIOSurfaceMac::DrawIOSurface(
     CHECK_AND_SAVE_GL_ERROR();
   } else {
     // Should match the clear color of RenderWidgetHostViewMac.
-    glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
+    glClearColor(0, 0, 0, 0);
     glClear(GL_COLOR_BUFFER_BIT);
   }
 
diff --git renderer_host/render_widget_host_view_aura.cc renderer_host/render_widget_host_view_aura.cc
index 6ad6e41..9f33679 100644
--- renderer_host/render_widget_host_view_aura.cc
+++ renderer_host/render_widget_host_view_aura.cc
@@ -1706,8 +1706,14 @@ void RenderWidgetHostViewAura::OnPaint(gfx::Canvas* canvas) {
   // For non-opaque windows, we don't draw anything, since we depend on the
   // canvas coming from the compositor to already be initialized as
   // transparent.
-  if (window_->layer()->fills_bounds_opaquely())
-    canvas->DrawColor(SK_ColorWHITE);
+  if (window_->layer()->fills_bounds_opaquely()) {
+    if (host_->IsRenderView()) {
+      canvas->DrawColor(GetContentClient()->browser()->GetBaseBackgroundColor(
+          RenderViewHost::From(host_)));
+    } else {
+      canvas->DrawColor(SK_ColorWHITE);
+    }
+  }
 }
 
 void RenderWidgetHostViewAura::OnDeviceScaleFactorChanged(
diff --git renderer_host/render_widget_host_view_mac.mm renderer_host/render_widget_host_view_mac.mm
index 0d4d03c..8615203 100644
--- renderer_host/render_widget_host_view_mac.mm
+++ renderer_host/render_widget_host_view_mac.mm
@@ -541,7 +541,7 @@ RenderWidgetHostViewMac::RenderWidgetHostViewMac(RenderWidgetHost* widget)
   // draw.
   background_layer_.reset([[CALayer alloc] init]);
   [background_layer_
-      setBackgroundColor:CGColorGetConstantColor(kCGColorWhite)];
+      setBackgroundColor:CGColorGetConstantColor(kCGColorClear)];
   [cocoa_view_ setLayer:background_layer_];
   [cocoa_view_ setWantsLayer:YES];