Fix use_image_texture_target inconsistencies

cc/output/buffer_to_texture_target_map.cc

Index: cc/output/buffer_to_texture_target_map.cc
diff --git a/cc/output/buffer_to_texture_target_map.cc b/cc/output/buffer_to_texture_target_map.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0abd7bf5951958323b50770478ee090a118f65aa
--- /dev/null
+++ b/cc/output/buffer_to_texture_target_map.cc
@@ -0,0 +1,73 @@
+// Copyright 2016 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 "cc/output/buffer_to_texture_target_map.h"
+
+#include <vector>
+
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
+#include "gpu/GLES2/gl2extchromium.h"
+
+namespace cc {
+
+BufferToTextureTargetMap StringToBufferToTextureTargetMap(
+    const std::string& str) {
+  BufferToTextureTargetMap map;
+  std::vector<std::string> entries =
+      base::SplitString(str, ";", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
+  for (const auto& entry : entries) {
+    std::vector<std::string> fields = base::SplitString(
+        entry, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
+    CHECK_EQ(fields.size(), 3);
+    uint32_t usage = 0;
+    uint32_t format = 0;
+    uint32_t target = 0;
+    bool succeeded = base::StringToUint(fields[0], &usage) &&
+                     base::StringToUint(fields[1], &format) &&
+                     base::StringToUint(fields[2], &target);
+    CHECK(succeeded);
+    CHECK_LE(usage, static_cast<uint32_t>(gfx::BufferUsage::LAST));
+    CHECK_LE(format, static_cast<uint32_t>(gfx::BufferFormat::LAST));
+    map.emplace(
+        BufferToTextureTargetKey(static_cast<gfx::BufferUsage>(usage),
+                                 static_cast<gfx::BufferFormat>(format)),
+        target);
+  }
+  return map;
+}
+
+std::string BufferToTextureTargetMapToString(
+    const BufferToTextureTargetMap& map) {
+  std::string str;
+  for (const auto& entry : map) {
+    if (!str.empty())
+      str += ";";
+    str += base::UintToString(static_cast<uint32_t>(entry.first.first));
+    str += ",";
+    str += base::UintToString(static_cast<uint32_t>(entry.first.second));
+    str += ",";
+    str += base::UintToString(entry.second);
+  }
+  return str;
+}
+
+BufferToTextureTargetMap DefaultBufferToTextureTargetMapForTesting() {
+  BufferToTextureTargetMap image_targets;
+  for (size_t usage_idx = 0;
+       usage_idx < static_cast<size_t>(gfx::BufferUsage::LAST) + 1;
+       ++usage_idx) {
+    gfx::BufferUsage usage = static_cast<gfx::BufferUsage>(usage_idx);
+    for (size_t format_idx = 0;
+         format_idx < static_cast<size_t>(gfx::BufferFormat::LAST) + 1;
+         ++format_idx) {
+      gfx::BufferFormat format = static_cast<gfx::BufferFormat>(format_idx);
+      image_targets.emplace(BufferToTextureTargetKey(usage, format),
+                            GL_TEXTURE_2D);
+    }
+  }
+
+  return image_targets;
+}
+
+}  // namespace cc