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

src/core/SkPicture.cpp

Index: src/core/SkPicture.cpp
===================================================================
--- src/core/SkPicture.cpp	(revision 8043)
+++ src/core/SkPicture.cpp	(working copy)
@@ -320,6 +320,9 @@
     if (8 == sizeof(void*)) {
         info.fFlags |= SkPictInfo::kPtrIs64Bit_Flag;
     }
+    if (NULL != playback && playback->hasRecordedBounds()) {
+        info.fFlags |= SkPictInfo::kHasRecordedBounds_Flag;
+    }
 
     stream->write(&info, sizeof(info));
     if (playback) {