Adding option in SkPicture to record device-space bounds of draw commands.

include/core/SkPicture.h

Index: include/core/SkPicture.h
===================================================================
--- include/core/SkPicture.h	(revision 8010)
+++ include/core/SkPicture.h	(working copy)
@@ -89,7 +89,7 @@
     void clone(SkPicture* pictures, int count) const;
 
     enum RecordingFlags {
-        /*  This flag specifies that when clipPath() is called, the path will
+        /** This flag specifies that when clipPath() is called, the path will
             be faithfully recorded, but the recording canvas' current clip will
             only see the path's bounds. This speeds up the recording process
             without compromising the fidelity of the playback. The only side-
@@ -98,7 +98,7 @@
             path.
          */
         kUsePathBoundsForClip_RecordingFlag = 0x01,
-        /*  This flag causes the picture to compute bounding boxes and build
+        /** This flag causes the picture to compute bounding boxes and build
             up a spatial hierarchy (currently an R-Tree), plus a tree of Canvas'
             usually stack-based clip/etc state. This requires an increase in
             recording time (often ~2x; likely more for very complex pictures),
@@ -115,7 +115,12 @@
             Note: Currently this is not serializable, the bounding data will be
             discarded if you serialize into a stream and then deserialize.
         */
-        kOptimizeForClippedPlayback_RecordingFlag = 0x02
+        kOptimizeForClippedPlayback_RecordingFlag = 0x02,
+        /** This flag causes device-space bounding boxes to be stored for
+            each canvas call that writes pixels. Encoding this information
+            enables several playback optimizations.
+        */
+        kRecordBounds_RecordingFlag = 0x04
     };
 
     /** Returns the canvas that records the drawing commands.