GM: add --writeChecksumBasedFilenames option

gm/gmmain.cpp

Index: gm/gmmain.cpp
===================================================================
--- gm/gmmain.cpp	(revision 9460)
+++ gm/gmmain.cpp	(working copy)
@@ -1303,9 +1303,11 @@
 DEFINE_bool(tileGrid, true, "Exercise the tile grid variant of SkPicture.");
 DEFINE_string(tileGridReplayScales, "", "Space separated list of floating-point scale "
               "factors to be used for tileGrid playback testing. Default value: 1.0");
-DEFINE_string(writeJsonSummaryPath, "", "Write a JSON-formatted result summary to this file.");
 DEFINE_bool2(verbose, v, false, "Give more detail (e.g. list all GMs run, more info about "
              "each test).");
+DEFINE_bool(writeChecksumBasedFilenames, false, "When writing out actual images, use checksum-"

[epoger, 2013/06/18 03:44:10]

Patchset 1 adds the definition of the new flag, but doesn't actually modify GM's
behavior based on the presence of the flag.

+            "based filenames, as rebaseline.py will use when downloading them from Google Storage");
+DEFINE_string(writeJsonSummaryPath, "", "Write a JSON-formatted result summary to this file.");
 DEFINE_string2(writePath, w, "",  "Write rendered images into this directory.");
 DEFINE_string2(writePicturePath, p, "", "Write .skp files into this directory.");
 DEFINE_int32(pdfJpegQuality, -1, "Encodes images in JPEG at quality level N, "