Chromium compositor change implementing page-scale driven pinch-zoom.

cc/CCSettings.h

Index: cc/CCSettings.h
===================================================================
--- cc/CCSettings.h	(revision 158365)
+++ cc/CCSettings.h	(working copy)
@@ -14,6 +14,7 @@
     static bool perTilePaintingEnabled();
     static bool partialSwapEnabled();
     static bool acceleratedAnimationEnabled();
+    static bool pageScalePinchZoomEnabled();
 
     // These setters should only be used on the main thread before the layer
     // renderer is initialized.
@@ -21,6 +22,11 @@
     static void setPartialSwapEnabled(bool);
     static void setAcceleratedAnimationEnabled(bool);
 
+    // Page-Scale pinch-zoom is normally controlled by a command line argument:
+    //   switches::kEnablePinchInCompositor
+    // It can also be enabled here, for use in tests.
+    static void setPageScalePinchZoomEnabled(bool);
+
     // These settings are meant to be set only once, and only read thereafter.
     // This function is only for resetting settings in tests.
     static void reset();