[SystemInfo API] Implement systemInfo.storage.onAvailableCapacityChanged event

chrome/browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc

Index: chrome/browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc
diff --git a/chrome/browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc b/chrome/browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc
index ebb573297ee5d4343bebcc060f4e3c6263cc4071..3bc890a32f19442ee06495508a7d9a458192fa9b 100644
--- a/chrome/browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc
+++ b/chrome/browser/extensions/api/system_info_storage/storage_info_provider_unittest.cc
@@ -44,7 +44,7 @@ const size_t kWatchingIntervalMs = 1u;
 // The number of times of checking watched storages.
 const int kCheckTimes = 10;
 
-class MockStorageObserver : public StorageInfoProvider::Observer {
+class MockStorageObserver : public StorageInfoObserver {
  public:
   MockStorageObserver() {}
   virtual ~MockStorageObserver() {}
@@ -59,7 +59,7 @@ class MockStorageObserver : public StorageInfoProvider::Observer {
 // A testing observer used to provide the statistics of how many times
 // that the storage free space has been changed and check the change against
 // our expectation.
-class TestStorageObserver : public StorageInfoProvider::Observer {
+class TestStorageObserver : public StorageInfoObserver {
  public:
   TestStorageObserver() {
     for (size_t i = 0; i < arraysize(kTestingData); ++i)