gpu: support RG_88 GpuMemoryBuffer

ui/gl/gl_image_io_surface.mm

Index: ui/gl/gl_image_io_surface.mm
diff --git a/ui/gl/gl_image_io_surface.mm b/ui/gl/gl_image_io_surface.mm
index b5210c4fee5f99824e200ad56db8026c06e10dc4..7c7000c439a8c6d68f51b32838b9344024c6000b 100644
--- a/ui/gl/gl_image_io_surface.mm
+++ b/ui/gl/gl_image_io_surface.mm
@@ -33,6 +33,7 @@ namespace {
 bool ValidInternalFormat(unsigned internalformat) {
   switch (internalformat) {
     case GL_RED:
+    case GL_RG:
     case GL_BGRA_EXT:
     case GL_RGB:
     case GL_RGB_YCBCR_420V_CHROMIUM:
@@ -53,6 +54,7 @@ bool ValidFormat(gfx::BufferFormat format) {
     case gfx::BufferFormat::UYVY_422:
     case gfx::BufferFormat::YUV_420_BIPLANAR:
       return true;
+    case gfx::BufferFormat::RG_88:
     case gfx::BufferFormat::ATC:
     case gfx::BufferFormat::ATCIA:
     case gfx::BufferFormat::DXT1:
@@ -73,6 +75,8 @@ GLenum TextureFormat(gfx::BufferFormat format) {
   switch (format) {
     case gfx::BufferFormat::R_8:
       return GL_RED;
+    case gfx::BufferFormat::RG_88:
+      return GL_RG;
     case gfx::BufferFormat::BGRA_8888:
     case gfx::BufferFormat::BGRX_8888:
     case gfx::BufferFormat::RGBA_8888:
@@ -102,6 +106,8 @@ GLenum DataFormat(gfx::BufferFormat format) {
   switch (format) {
     case gfx::BufferFormat::R_8:
       return GL_RED;
+    case gfx::BufferFormat::RG_88:
+      return GL_RG;
     case gfx::BufferFormat::BGRA_8888:
     case gfx::BufferFormat::BGRX_8888:
     case gfx::BufferFormat::RGBA_8888:
@@ -129,6 +135,7 @@ GLenum DataFormat(gfx::BufferFormat format) {
 GLenum DataType(gfx::BufferFormat format) {
   switch (format) {
     case gfx::BufferFormat::R_8:
+    case gfx::BufferFormat::RG_88:
       return GL_UNSIGNED_BYTE;
     case gfx::BufferFormat::BGRA_8888:
     case gfx::BufferFormat::BGRX_8888: