gpu: Expose internal format R8 instead of RED.

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 3059333cc8896feb96c15f2b4147e3e927a3f417..2ae58ef5bb37d212dd95d14f1743cb8f852f41ed 100644
--- a/ui/gl/gl_image_io_surface.mm
+++ b/ui/gl/gl_image_io_surface.mm
@@ -16,6 +16,7 @@
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_helper.h"
+#include "ui/gl/gl_version_info.h"
 #include "ui/gl/scoped_binders.h"
 
 // Note that this must be included after gl_bindings.h to avoid conflicts.
@@ -68,7 +69,7 @@ STRINGIZE(
 
 bool ValidInternalFormat(unsigned internalformat) {
   switch (internalformat) {
-    case GL_RED:
+    case GL_R8:
     case GL_BGRA_EXT:
     case GL_RGB:
     case GL_RGB_YCBCR_420V_CHROMIUM:
@@ -106,8 +107,16 @@ bool ValidFormat(BufferFormat format) {
 
 GLenum TextureFormat(BufferFormat format) {
   switch (format) {
-    case BufferFormat::R_8:
-      return GL_RED;
+    case BufferFormat::R_8: {
+      const gfx::GLVersionInfo* version_info =

[reveman, 2016/02/20 01:07:55]

Can this case be implemented this way?

return gfx::GLContext::GetCurrent()->GetVersionInfo()->IsES3Capable()
    ? GL_R8 : GL_RED;

[Daniele Castagna, 2016/02/20 01:16:16]

Done.

+          gfx::GLContext::GetCurrent()->GetVersionInfo();
+      if (version_info->IsAtLeastGL(3, 0) ||
+          version_info->IsAtLeastGLES(3, 0)) {
+        return GL_R8;
+      } else {
+        return GL_RED;
+      }
+    }
     case BufferFormat::BGRA_8888:
     case BufferFormat::RGBA_8888:
       return GL_RGBA;