Disable bad gif decode on CG

tools/dm_flags.py

Index: tools/dm_flags.py
diff --git a/tools/dm_flags.py b/tools/dm_flags.py
index 0de32fce817898f4ca39f5965daab7ea52f8eda7..2e3ba7fd86a5a0b45d10407e0104ee1f9e5e6c26 100755
--- a/tools/dm_flags.py
+++ b/tools/dm_flags.py
@@ -113,8 +113,8 @@ def get_args(bot):
     blacklist.extend('_ image _ interlaced2.png'.split(' '))
     blacklist.extend('_ image _ interlaced3.png'.split(' '))
 
-  # CG fails on questionable bmps
   if 'Mac' in bot or 'iOS' in bot:
+    # CG fails on questionable bmps
     blacklist.extend('_ image gen_platf rgba32abf.bmp'.split(' '))
     blacklist.extend('_ image gen_platf rgb24prof.bmp'.split(' '))
     blacklist.extend('_ image gen_platf rgb24lprof.bmp'.split(' '))
@@ -122,6 +122,10 @@ def get_args(bot):
     blacklist.extend('_ image gen_platf 4bpp-pixeldata-cropped.bmp'.split(' '))
     blacklist.extend('_ image gen_platf 32bpp-pixeldata-cropped.bmp'.split(' '))
     blacklist.extend('_ image gen_platf 24bpp-pixeldata-cropped.bmp'.split(' '))
+    
+    # CG has unpredictable behavior on this questionable gif
+    # It's probably using uninitialized memory
+    blacklist.extend('_ image gen_platf frame_larger_than_image.gif'.split(' '))
 
   # skia:4095
   for test in ['not_native32_bitmap_config',