Plumb can_use_lcd_text, contents_opaque directly to ContentLayerClient.

cc/layers/content_layer.cc

Index: cc/layers/content_layer.cc
diff --git a/cc/layers/content_layer.cc b/cc/layers/content_layer.cc
index d3e9a2873a8f77e482e9ab645d5d326ad175e1e5..b0c8bf41bcfd4ebd48808f5b2e28104ffec118eb 100644
--- a/cc/layers/content_layer.cc
+++ b/cc/layers/content_layer.cc
@@ -25,9 +25,13 @@ scoped_ptr<ContentLayerPainter> ContentLayerPainter::Create(
 }
 
 void ContentLayerPainter::Paint(SkCanvas* canvas,
-                                const gfx::Rect& content_rect) {
+                                const gfx::Rect& content_rect,
+                                bool can_use_lcd_text,
+                                bool contents_opaque) {
   client_->PaintContents(canvas,
                          content_rect,
+                         can_use_lcd_text,
+                         contents_opaque,
                          ContentLayerClient::GRAPHICS_CONTEXT_ENABLED);
 }
 
@@ -38,7 +42,8 @@ scoped_refptr<ContentLayer> ContentLayer::Create(ContentLayerClient* client) {
 ContentLayer::ContentLayer(ContentLayerClient* client)
     : TiledLayer(),
       client_(client),
-      can_use_lcd_text_last_frame_(can_use_lcd_text()) {
+      can_use_lcd_text_last_frame_(false),
+      first_update_lcd_text_occured_(false) {
 }
 
 ContentLayer::~ContentLayer() {}
@@ -127,12 +132,18 @@ void ContentLayer::SetContentsOpaque(bool opaque) {
 }
 
 void ContentLayer::UpdateCanUseLCDText() {
-  if (can_use_lcd_text_last_frame_ == can_use_lcd_text())
-    return;
+  if (first_update_lcd_text_occured_) {
+    if (can_use_lcd_text_last_frame_ == can_use_lcd_text())
+      return;
+    // LCD text can turn off but never on.
+    if (!can_use_lcd_text_last_frame_)
+      return;
+  }
 
   can_use_lcd_text_last_frame_ = can_use_lcd_text();
-  if (client_)
-    client_->DidChangeLayerCanUseLCDText();

[enne (OOO), 2014/11/12 18:51:05]

I don't think this can go.  The reason this was implemented in
WebContentLayerImpl and not inside of this function is because Blink wanted
invalidations and ui::Layer did not.  ui::Layer never wants invalidations when
lcd changes.

[danakj, 2014/11/12 18:52:48]

Ah okay, makes sense now that I saw the ui::Layer differences. Thanks.

+  updater_->SetCanUseLCDText(can_use_lcd_text_last_frame_);
+  first_update_lcd_text_occured_ = true;
+  SetNeedsDisplay();
 }
 
 bool ContentLayer::SupportsLCDText() const {
@@ -150,6 +161,8 @@ skia::RefPtr<SkPicture> ContentLayer::GetPicture() const {
   SkCanvas* canvas = recorder.beginRecording(width, height, nullptr, 0);
   client_->PaintContents(canvas,
                          gfx::Rect(width, height),
+                         can_use_lcd_text_last_frame_,
+                         contents_opaque(),
                          ContentLayerClient::GRAPHICS_CONTEXT_ENABLED);
   skia::RefPtr<SkPicture> picture = skia::AdoptRef(recorder.endRecording());
   return picture;