cc: Implement overdraw feedback debugging feature.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 92049d87610d170e1bd521494cc6fcf09e89d372..8d48276a47c6976b888999927205e914d29f0538 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -5536,6 +5536,12 @@ Keep your key file in a safe place. You will need it to create new versions of y
       <message name="IDS_FLAGS_GL_COMPOSITED_TEXTURE_QUAD_BORDERS_DESCRIPTION" desc="Description of the 'Composited layer borders' lab.">
         Renders a border around GL composited texture quads to help debug and study overlay support.
       </message>
+      <message name="IDS_FLAGS_OVERDRAW_FEEDBACK" desc="Name of the 'Overdraw feedback' lab.">
+        Overdraw feedback
+      </message>
+      <message name="IDS_FLAGS_OVERDRAW_FEEDBACK_DESCRIPTION" desc="Description of the 'Overdraw feedback' lab.">
+        Visualize overdraw by color-coding elements based on if they have other elements drawn underneath.
+      </message>
       <message name="IDS_FLAGS_DEBUG_SHORTCUTS_NAME" desc="Name of the 'Debugging keyboard shortcuts' lab.">
         Debugging keyboard shortcuts
       </message>