Add a warning when developing an extension that uses old manifest version.

chrome/common/extensions/manifest_unittest.cc

 // Copyright (c) 2012 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 "chrome/common/extensions/manifest.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 
@@ skipping 47 matching lines @@
   scoped_ptr<DictionaryValue> manifest_value(new DictionaryValue());
   manifest_value->SetString(keys::kName, "extension");
   manifest_value->SetString(keys::kVersion, "1");
   // Only supported in manifest_version=1.
   manifest_value->SetString(keys::kBackgroundPageLegacy, "bg.html");
   manifest_value->SetString("unknown_key", "foo");
 
   scoped_ptr<Manifest> manifest(
       new Manifest(Extension::INTERNAL, manifest_value.Pass()));
   std::string error;
-  std::vector<std::string> warnings;
+  Extension::InstallWarningVector warnings;
   manifest->ValidateManifest(&error, &warnings);
   EXPECT_TRUE(error.empty());
   ASSERT_EQ(1u, warnings.size());
   AssertType(manifest.get(), Extension::TYPE_EXTENSION);
 
   // The known key 'background_page' should be accessible.
   std::string value;
   EXPECT_TRUE(manifest->GetString(keys::kBackgroundPageLegacy, &value));
   EXPECT_EQ("bg.html", value);
 
@@ skipping 12 matching lines @@
   // Validate should also give a warning.
   warnings.clear();
   manifest->ValidateManifest(&error, &warnings);
   EXPECT_TRUE(error.empty());
   ASSERT_EQ(2u, warnings.size());
   {
     Feature feature;
     feature.set_name("background_page");
     feature.set_max_manifest_version(1);
     EXPECT_EQ(feature.GetErrorMessage(Feature::INVALID_MAX_MANIFEST_VERSION),
-              warnings[0]);
+              warnings[0].message);
   }
 
   // Test DeepCopy and Equals.
   scoped_ptr<Manifest> manifest2(manifest->DeepCopy());
   EXPECT_TRUE(manifest->Equals(manifest2.get()));
   EXPECT_TRUE(manifest2->Equals(manifest.get()));
   MutateManifest(
       &manifest, "foo", Value::CreateStringValue("blah"));
   EXPECT_FALSE(manifest->Equals(manifest2.get()));
 }
 
 // Verifies that key restriction based on type works.
 TEST_F(ManifestTest, ExtensionTypes) {
   scoped_ptr<DictionaryValue> value(new DictionaryValue());
   value->SetString(keys::kName, "extension");
   value->SetString(keys::kVersion, "1");
 
   scoped_ptr<Manifest> manifest(
       new Manifest(Extension::INTERNAL, value.Pass()));
   std::string error;
-  std::vector<std::string> warnings;
+  Extension::InstallWarningVector warnings;
   manifest->ValidateManifest(&error, &warnings);
   EXPECT_TRUE(error.empty());
   EXPECT_TRUE(warnings.empty());
 
   // By default, the type is Extension.
   AssertType(manifest.get(), Extension::TYPE_EXTENSION);
 
   // Theme.
   MutateManifest(
       &manifest, keys::kTheme, new DictionaryValue());
@@ skipping 28 matching lines @@
 
 // Verifies that the getters filter restricted keys.
 TEST_F(ManifestTest, RestrictedKeys) {
   scoped_ptr<DictionaryValue> value(new DictionaryValue());
   value->SetString(keys::kName, "extension");
   value->SetString(keys::kVersion, "1");
 
   scoped_ptr<Manifest> manifest(
       new Manifest(Extension::INTERNAL, value.Pass()));
   std::string error;
-  std::vector<std::string> warnings;
+  Extension::InstallWarningVector warnings;
   manifest->ValidateManifest(&error, &warnings);
   EXPECT_TRUE(error.empty());
   EXPECT_TRUE(warnings.empty());
 
   // Platform apps cannot have a "page_action" key.
   MutateManifest(
       &manifest, keys::kPageAction, new DictionaryValue());
   AssertType(manifest.get(), Extension::TYPE_EXTENSION);
   base::Value* output = NULL;
   EXPECT_TRUE(manifest->HasKey(keys::kPageAction));
@@ skipping 13 matching lines @@
   EXPECT_FALSE(manifest->HasKey(keys::kCommands));
   EXPECT_FALSE(manifest->Get(keys::kCommands, &output));
 
   MutateManifest(
       &manifest, keys::kManifestVersion, Value::CreateIntegerValue(2));
   EXPECT_TRUE(manifest->HasKey(keys::kCommands));
   EXPECT_TRUE(manifest->Get(keys::kCommands, &output));
 };
 
 }  // namespace extensions