Add RGBA half float texture format.

src/gpu/gl/GrGLDefines.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 
 #ifndef GrGLDefines_DEFINED
@@ skipping 386 matching lines @@
 #define GR_GL_RGB                            0x1907
 #define GR_GL_RGBA                           0x1908
 #define GR_GL_BGRA                           0x80E1
 #define GR_GL_LUMINANCE                      0x1909
 #define GR_GL_LUMINANCE_ALPHA                0x190A
 #define GR_GL_PALETTE8_RGBA8                 0x8B96
 #define GR_GL_ALPHA8                         0x803C
 
 #define GR_GL_R8                             0x8229
 #define GR_GL_R16F                           0x822D
+#define GR_GL_RGBA16F                        0x881A
 #define GR_GL_ALPHA16F                       0x881C
 
 /* PixelType */
 /*      GL_UNSIGNED_BYTE */
 #define GR_GL_UNSIGNED_SHORT_4_4_4_4         0x8033
 #define GR_GL_UNSIGNED_SHORT_5_5_5_1         0x8034
 #define GR_GL_UNSIGNED_SHORT_5_6_5           0x8363
 
 /* Shaders */
 #define GR_GL_FRAGMENT_SHADER                  0x8B30
@@ skipping 456 matching lines @@
 // NV_path_rendering extension to EXT_direct_state_access:
 // [the matrix functions] must support the PATH_PROJECTION_NV and
 // PATH_MODELVIEW_NV tokens for matrixMode.
 #define GR_GL_PATH_PROJECTION                               0x1701
 #define GR_GL_PATH_MODELVIEW                                0x1700
 
 /*  ARM specific define for MSAA support on framebuffer fetch */
 #define GR_GL_FETCH_PER_SAMPLE_ARM                          0x8F65
 
 #endif