Reland cmaa, gpu: use R8 image texture when GL_NV_image_formats is available.

gpu/command_buffer/service/feature_info.cc

Index: gpu/command_buffer/service/feature_info.cc
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index 3eaf1adc7f807bf7acf43dc5d1131cf78730e019..4c2c50ea4ddbac07247e9e5c422c3a890e84b2c6 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -913,6 +913,7 @@ void FeatureInfo::InitializeFeatures() {
              (gl_version_info_->IsAtLeastGLES(3, 1) ||
               (gl_version_info_->IsAtLeastGL(3, 0) &&
                extensions.Contains("GL_ARB_shading_language_420pack") &&
+               extensions.Contains("GL_ARB_texture_storage") &&
                extensions.Contains("GL_ARB_texture_gather") &&
                extensions.Contains("GL_ARB_explicit_uniform_location") &&
                extensions.Contains("GL_ARB_explicit_attrib_location") &&