Add command line flags for compositor's default tile size and

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
===================================================================
--- content/browser/web_contents/web_contents_impl.cc	(revision 137957)
+++ content/browser/web_contents/web_contents_impl.cc	(working copy)
@@ -220,6 +220,18 @@
     delegate->AddNavigationHeaders(params->url, &params->extra_headers);
 }
 
+int GetSwitchValueAsInt(
+    const CommandLine& command_line,
+    const std::string& switch_string,
+    int min_value) {
+  std::string string_value = command_line.GetSwitchValueASCII(switch_string);
+  int int_value;
+  if (base::StringToInt(string_value, &int_value))
+    return std::max(min_value, int_value);
+  else
+    return min_value;
+}
+
 }  // namespace
 
 namespace content {
@@ -515,6 +527,19 @@
   }
 #endif
 
+  if (command_line.HasSwitch(switches::kDefaultTileWidth))
+    prefs.default_tile_width =
+        GetSwitchValueAsInt(command_line, switches::kDefaultTileWidth, 1);
+  if (command_line.HasSwitch(switches::kDefaultTileHeight))
+    prefs.default_tile_height =
+        GetSwitchValueAsInt(command_line, switches::kDefaultTileHeight, 1);
+  if (command_line.HasSwitch(switches::kMaxUntiledLayerWidth))
+    prefs.max_untiled_layer_width =
+        GetSwitchValueAsInt(command_line, switches::kMaxUntiledLayerWidth, 1);
+  if (command_line.HasSwitch(switches::kMaxUntiledLayerHeight))
+    prefs.max_untiled_layer_height =
+        GetSwitchValueAsInt(command_line, switches::kMaxUntiledLayerHeight, 1);
+
   content::GetContentClient()->browser()->OverrideWebkitPrefs(rvh, url, &prefs);
 
   return prefs;