Fix blurry content after disabling dev tools emulation

cc/trees/layer_tree_host.h

Index: cc/trees/layer_tree_host.h
diff --git a/cc/trees/layer_tree_host.h b/cc/trees/layer_tree_host.h
index 3a4454746a31c5483251e0903de794e29fccdbfa..5f02fefd5ddf32cb419676151a8fc1c9cc6b2012 100644
--- a/cc/trees/layer_tree_host.h
+++ b/cc/trees/layer_tree_host.h
@@ -119,6 +119,9 @@ class CC_EXPORT LayerTreeHost {
   // synchronization.
   virtual void SetNeedsCommit() = 0;
 
+  // Requests that the next frame re-chooses crisp raster scales for all layers.
+  virtual void SetNeedsRecalculateRasterScales() = 0;
+
   // Returns true if a main frame (for any pipeline stage above) has been
   // requested.
   virtual bool BeginMainFrameRequested() const = 0;