[content] Fix background color update handling in RWHVAura.

content/browser/renderer_host/render_widget_host_view_android.cc

Index: content/browser/renderer_host/render_widget_host_view_android.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_android.cc b/content/browser/renderer_host/render_widget_host_view_android.cc
index 90cd9523e338a2066b975f0ef15d4a8844855b0a..8e5da0cd23863eaaea4c3bd62eab2baf446ee33f 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -452,6 +452,7 @@ RenderWidgetHostViewAndroid::RenderWidgetHostViewAndroid(
       is_in_vr_(false),
       content_view_core_(nullptr),
       ime_adapter_android_(nullptr),
+      background_color_(SK_ColorWHITE),
       cached_background_color_(SK_ColorWHITE),
       view_(this),
       gesture_provider_(ui::GetGestureProviderConfig(
@@ -1038,11 +1039,18 @@ void RenderWidgetHostViewAndroid::SetTooltipText(
 }
 
 void RenderWidgetHostViewAndroid::SetBackgroundColor(SkColor color) {
-  RenderWidgetHostViewBase::SetBackgroundColor(color);
-  host_->SetBackgroundOpaque(GetBackgroundOpaque());
+  background_color_ = color;
+
+  DCHECK(SkColorGetA(color) == SK_AlphaOPAQUE ||
+         SkColorGetA(color) == SK_AlphaTRANSPARENT);
+  host_->SetBackgroundOpaque(SkColorGetA(color) == SK_AlphaOPAQUE);
   UpdateBackgroundColor(color);
 }
 
+SkColor RenderWidgetHostViewAndroid::background_color() const {
+  return background_color_;
+}
+
 void RenderWidgetHostViewAndroid::CopyFromSurface(
     const gfx::Rect& src_subrect,
     const gfx::Size& dst_size,