Extension Storage API: expose storage quota information to extensions, via:

chrome/browser/extensions/settings/settings_quota_unittest.cc

Index: chrome/browser/extensions/settings/settings_quota_unittest.cc
diff --git a/chrome/browser/extensions/settings/settings_quota_unittest.cc b/chrome/browser/extensions/settings/settings_quota_unittest.cc
index 0cb4c19a584fb6e9a30e86f32d550603378abbed..6314c47110f8b81a63f75c7e225bb6909815073a 100644
--- a/chrome/browser/extensions/settings/settings_quota_unittest.cc
+++ b/chrome/browser/extensions/settings/settings_quota_unittest.cc
@@ -49,10 +49,10 @@ class ExtensionSettingsQuotaTest : public testing::Test {
  protected:
   // Creates |storage_|.  Must only be called once.
   void CreateStorage(
-      size_t quota_bytes, size_t quota_bytes_per_setting, size_t max_keys) {
+      size_t quota_bytes, size_t quota_bytes_per_item, size_t max_items) {
     ASSERT_TRUE(storage_.get() == NULL);
     SettingsStorageQuotaEnforcer::Limits limits =
-        { quota_bytes, quota_bytes_per_setting, max_keys };
+        { quota_bytes, quota_bytes_per_item, max_items };
     storage_.reset(new SettingsStorageQuotaEnforcer(limits, delegate_));
   }
 
@@ -557,4 +557,39 @@ TEST_F(ExtensionSettingsQuotaTest,
   EXPECT_TRUE(SettingsEqual(settings));
 }
 
+TEST_F(ExtensionSettingsQuotaTest, GetBytesInUse) {
+  // Just testing GetBytesInUse, no need for a quota.
+  CreateStorage(UINT_MAX, UINT_MAX, UINT_MAX);
+
+  std::vector<std::string> ab;
+  ab.push_back("a");
+  ab.push_back("b");
+
+  EXPECT_EQ(0u, storage_->GetBytesInUse());
+  EXPECT_EQ(0u, storage_->GetBytesInUse("a"));
+  EXPECT_EQ(0u, storage_->GetBytesInUse("b"));
+  EXPECT_EQ(0u, storage_->GetBytesInUse(ab));
+
+  storage_->Set(DEFAULTS, "a", *byte_value_1_);
+
+  EXPECT_EQ(2u, storage_->GetBytesInUse());
+  EXPECT_EQ(2u, storage_->GetBytesInUse("a"));
+  EXPECT_EQ(0u, storage_->GetBytesInUse("b"));
+  EXPECT_EQ(2u, storage_->GetBytesInUse(ab));
+
+  storage_->Set(DEFAULTS, "b", *byte_value_1_);
+
+  EXPECT_EQ(4u, storage_->GetBytesInUse());
+  EXPECT_EQ(2u, storage_->GetBytesInUse("a"));
+  EXPECT_EQ(2u, storage_->GetBytesInUse("b"));
+  EXPECT_EQ(4u, storage_->GetBytesInUse(ab));
+
+  storage_->Set(DEFAULTS, "c", *byte_value_1_);
+
+  EXPECT_EQ(6u, storage_->GetBytesInUse());
+  EXPECT_EQ(2u, storage_->GetBytesInUse("a"));
+  EXPECT_EQ(2u, storage_->GetBytesInUse("b"));
+  EXPECT_EQ(4u, storage_->GetBytesInUse(ab));
+}
+
 }  // namespace extensions