Set the default discardable pool size for Android framework.

gyp/common_conditions.gypi

 # conditions used in both common.gypi and skia.gyp in chromium
 #
 {
   'defines': [
     'SK_ALLOW_STATIC_GLOBAL_INITIALIZERS=<(skia_static_initializers)',
     'SK_SUPPORT_GPU=<(skia_gpu)',
     'SK_SUPPORT_OPENCL=<(skia_opencl)',
     'SK_FORCE_DISTANCEFIELD_FONTS=<(skia_force_distancefield_fonts)',
   ],
   'conditions' : [
@@ skipping 301 matching lines @@
         'SK_SUPPORT_LEGACY_PICTURE_CAN_RECORD',
         'SK_SUPPORT_DEPRECATED_RECORD_FLAGS',
         'SK_SUPPORT_LEGACY_DERIVED_PICTURE_CLASSES',
         'SK_SUPPORT_LEGACY_PICTURE_HEADERS',
         'SK_SUPPORT_LEGACY_BLURMASKFILTER_STYLE',
         # Needed until we fix skbug.com/2440.
         'SK_SUPPORT_LEGACY_CLIPTOLAYERFLAG',
         # Transitional, for deprecated SkCanvas::SaveFlags methods.
         'SK_ATTR_DEPRECATED=SK_NOTHING_ARG1',
         'SK_SUPPORT_LEGACY_SHADER_LOCALMATRIX',
+        'SK_DEFAULT_GLOBAL_DISCARDABLE_MEMORY_POOL_SIZE (512 * 1024)',
       ],
     }],
 
     [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris", "nacl", "chromeos"]',
       {
         'defines': [
           'SK_SAMPLES_FOR_X',
           'SK_BUILD_FOR_UNIX',
         ],
         'configurations': {
@@ skipping 322 matching lines @@
         'SK_BUILD_JSON_WRITER',
       ]
     }],
 
   ], # end 'conditions'
   # The Xcode SYMROOT must be at the root. See build/common.gypi in chromium for more details
   'xcode_settings': {
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }