Implement a NEON version of the RGBA gaussian blur. This shows a 9-15% speedup on Nexus-10.

gyp/opts.gyp

 {
   'targets': [
     # Due to an unfortunate intersection of lameness between gcc and gyp,
     # we have to build the *_SSE2.cpp files in a separate target.  The
     # gcc lameness is that, in order to compile SSE2 intrinsics code, it
     # must be passed the -msse2 flag.  However, with this flag, it may
     # emit SSE2 instructions even for scalar code, such as the CPUID
     # test used to test for the presence of SSE2.  So that, and all other
     # code must be compiled *without* -msse2.  The gyp lameness is that it
     # does not allow file-specific CFLAGS, so we must create this extra
@@ skipping 61 matching lines @@
           'variables': {
             'arm_neon_optional%': '<(arm_neon_optional>',
           },
           'sources': [
             '../src/opts/opts_check_arm.cpp',
             '../src/opts/memset.arm.S',
             '../src/opts/SkBitmapProcState_opts_arm.cpp',
             '../src/opts/SkBlitMask_opts_arm.cpp',
             '../src/opts/SkBlitRow_opts_arm.cpp',
             '../src/opts/SkBlitRow_opts_arm.h',
-            '../src/opts/SkBlurImage_opts_none.cpp',
             '../src/opts/SkXfermode_opts_arm.cpp',
           ],
           'conditions': [
             [ 'arm_neon == 1 or arm_neon_optional == 1', {
               'dependencies': [
                 'opts_neon',
               ]
             }],
             [ 'skia_os == "ios"', {
               'sources!': [
@@ skipping 79 matching lines @@
       ],
       'sources': [
         '../src/opts/memset16_neon.S',
         '../src/opts/memset32_neon.S',
         '../src/opts/SkBitmapProcState_arm_neon.cpp',
         '../src/opts/SkBitmapProcState_matrixProcs_neon.cpp',
         '../src/opts/SkBitmapProcState_matrix_clamp_neon.h',
         '../src/opts/SkBitmapProcState_matrix_repeat_neon.h',
         '../src/opts/SkBlitMask_opts_arm_neon.cpp',
         '../src/opts/SkBlitRow_opts_arm_neon.cpp',
+        '../src/opts/SkBlurImage_opts_neon.cpp',
         '../src/opts/SkMorphology_opts_neon.cpp',
         '../src/opts/SkXfermode_opts_arm_neon.cpp',
       ],
     },
   ],
 }