Lower ES3 capable requirement to GL 3.3 with extensions.

ui/gl/gl_version_info.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gl/gl_version_info.h"
 
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
@@ skipping 65 matching lines @@
     const std::set<std::string>& extensions) const {
   auto has_extension = [&extensions](std::string extension) -> bool {
     return extensions.find(extension) != extensions.end();
   };
 
   // Version ES3 capable without extensions needed.
   if (IsAtLeastGLES(3, 0) || IsAtLeastGL(4, 2)) {
     return true;
   }
 
-  // Don't try supporting ES3 on ES2, or desktop before 4.0.
-  if (is_es || !IsAtLeastGL(4, 0)) {
+  // Don't try supporting ES3 on ES2, or desktop before 3.3.
+  if (is_es || !IsAtLeastGL(3, 3)) {
     return false;
   }
 
-  bool has_tex_storage = has_extension("GL_ARB_texture_storage");
-  return has_tex_storage;
+  bool has_transform_feedback =
+      (IsAtLeastGL(4, 0) || has_extension("GL_ARB_transform_feedback2"));
+  bool has_sampler_indexing =
+      (IsAtLeastGL(4, 0) || has_extension("GL_ARB_gpu_shader5"));
+  bool has_tex_storage =
+      (IsAtLeastGL(4, 2) || has_extension("GL_ARB_texture_storage"));

[piman, 2016/10/28 20:01:21]

nit: you can skip IsAtLeastGL(4, 2), since it's always false if we get here (see
l.82-83).

[Zhenyao Mo, 2016/10/28 23:22:12]

Done.

+
+  // TODO(cwallez) check for texture related extensions. See crbug.com/623577
+
+  return (has_transform_feedback &&
+          has_sampler_indexing &&
+          has_tex_storage);
 }
 
 void GLVersionInfo::ParseVersionString(const char* version_str,
                                        unsigned* major_version,
                                        unsigned* minor_version,
                                        bool* is_es,
                                        bool* is_es2,
                                        bool* is_es3) {
   // Make sure the outputs are always initialized.
   *major_version = 0;
@@ skipping 18 matching lines @@
     }
   }
   if (*is_es && *major_version == 2)
     *is_es2 = true;
   if (*is_es && *major_version == 3)
     *is_es3 = true;
   DCHECK(major_version != 0);
 }
 
 }  // namespace gl