MIPS: added optimization for SkRGB16_Opaque_Blitter::blitMask

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 274 matching lines @@
             'conditions': [
               [ 'mips_arch_variant == "mips32r2"', {
                 'cflags': [
                   '-march=mips32r2',
                 ],
                 'conditions': [
                   [ 'mips_dsp == 1', {
                     'cflags': [
                       '-mdsp',
                     ],
+                    'defines': [
+                      'SK_MIPS_HAS_DSP',
+                    ],
                   }],
                   [ 'mips_dsp == 2', {
                     'cflags': [
                       '-mdspr2',
                     ],
                     'defines': [
-                      '__MIPS_HAVE_DSPR2',
+                      'SK_MIPS_HAS_DSP',
+                      'SK_MIPS_HAS_DSPR2',
                     ],
                   }],
                 ],
               }],
             ],
           }],
         ],
       },
     ],
 
@@ skipping 383 matching lines @@
     [ 'skia_crash_handler', {
       'defines': [ 'SK_CRASH_HANDLER' ],
     }],
 
   ], # end 'conditions'
   # The Xcode SYMROOT must be at the root. See build/common.gypi in chromium for more details
   'xcode_settings': {
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }