Add a new GetInstance() method for singleton classes, take 2.

This is a small step towards making all singleton classes use the Singleton<T> pattern within their code and not expect the callers to know about it.

This CL includes all files except those under chrome/browser, chrome/net, chrome/service and third_party/WebKit (these will be done in future CLs).

Suggested files to focus for reviewers:
- joi@ for files under src/ceee
- tommi@ for files under src/chrome_frame
- maruel@ for the rest of the files.

BUG=65298
TEST=all existing tests should continue to pass.

Review URL: http://codereview.chromium.org/5581008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@68577 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 18 insertions, 10 deletions

diff --git a/media/filters/ffmpeg_demuxer.cc b/media/filters/ffmpeg_demuxer.cc
index 1ab307e..3024050 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -391,7 +391,7 @@ void FFmpegDemuxer::InitializeTask(DataSource* data_source,
   data_source_ = data_source;
 
   // Add ourself to Protocol list and get our unique key.
-  std::string key = FFmpegGlue::get()->AddProtocol(this);
+  std::string key = FFmpegGlue::GetInstance()->AddProtocol(this);
 
   // Open FFmpeg AVFormatContext.
   DCHECK(!format_context_);
@@ -399,7 +399,7 @@ void FFmpegDemuxer::InitializeTask(DataSource* data_source,
   int result = av_open_input_file(&context, key.c_str(), NULL, 0, NULL);
 
   // Remove ourself from protocol list.
-  FFmpegGlue::get()->RemoveProtocol(this);
+  FFmpegGlue::GetInstance()->RemoveProtocol(this);
 
   if (result < 0) {
     host()->SetError(DEMUXER_ERROR_COULD_NOT_OPEN);
diff --git a/media/filters/ffmpeg_glue.cc b/media/filters/ffmpeg_glue.cc
index 6f637c3..663fff7 100644
--- a/media/filters/ffmpeg_glue.cc
+++ b/media/filters/ffmpeg_glue.cc
@@ -16,7 +16,7 @@ media::FFmpegURLProtocol* ToProtocol(void* data) {
 // FFmpeg protocol interface.
 int OpenContext(URLContext* h, const char* filename, int flags) {
   media::FFmpegURLProtocol* protocol;
-  media::FFmpegGlue::get()->GetProtocol(filename, &protocol);
+  media::FFmpegGlue::GetInstance()->GetProtocol(filename, &protocol);
   if (!protocol)
     return AVERROR_IO;
 
@@ -145,6 +145,11 @@ FFmpegGlue::~FFmpegGlue() {
   av_lockmgr_register(NULL);
 }
 
+// static
+FFmpegGlue* FFmpegGlue::GetInstance() {
+  return Singleton<FFmpegGlue>::get();
+}
+
 std::string FFmpegGlue::AddProtocol(FFmpegURLProtocol* protocol) {
   AutoLock auto_lock(lock_);
   std::string key = GetProtocolKey(protocol);
diff --git a/media/filters/ffmpeg_glue.h b/media/filters/ffmpeg_glue.h
index 1ae4ded..4f991d1 100644
--- a/media/filters/ffmpeg_glue.h
+++ b/media/filters/ffmpeg_glue.h
@@ -64,8 +64,11 @@ class FFmpegURLProtocol {
   DISALLOW_COPY_AND_ASSIGN(FFmpegURLProtocol);
 };
 
-class FFmpegGlue : public Singleton<FFmpegGlue> {
+class FFmpegGlue {
  public:
+  // Returns the singleton instance.
+  static FFmpegGlue* GetInstance();
+
   // Adds a FFmpegProtocol to the FFmpeg glue layer and returns a unique string
   // that can be passed to FFmpeg to identify the data source.
   std::string AddProtocol(FFmpegURLProtocol* protocol);
diff --git a/media/filters/ffmpeg_glue_unittest.cc b/media/filters/ffmpeg_glue_unittest.cc
index d217f9c..f823669 100644
--- a/media/filters/ffmpeg_glue_unittest.cc
+++ b/media/filters/ffmpeg_glue_unittest.cc
@@ -43,7 +43,7 @@ class FFmpegGlueTest : public ::testing::Test {
     MockFFmpeg::set(&mock_ffmpeg_);
 
     // Singleton should initialize FFmpeg.
-    CHECK(FFmpegGlue::get());
+    CHECK(FFmpegGlue::GetInstance());
 
     // Assign our static copy of URLProtocol for the rest of the tests.
     protocol_ = MockFFmpeg::protocol();
@@ -61,10 +61,10 @@ class FFmpegGlueTest : public ::testing::Test {
     EXPECT_CALL(*protocol, IsStreaming()).WillOnce(Return(true));
 
     // Add the protocol to the glue layer and open a context.
-    std::string key = FFmpegGlue::get()->AddProtocol(protocol);
+    std::string key = FFmpegGlue::GetInstance()->AddProtocol(protocol);
     memset(context, 0, sizeof(*context));
     EXPECT_EQ(0, protocol_->url_open(context, key.c_str(), 0));
-    FFmpegGlue::get()->RemoveProtocol(protocol);
+    FFmpegGlue::GetInstance()->RemoveProtocol(protocol);
   }
 
  protected:
@@ -90,7 +90,7 @@ TEST_F(FFmpegGlueTest, InitializeFFmpeg) {
 
 TEST_F(FFmpegGlueTest, AddRemoveGetProtocol) {
   // Prepare testing data.
-  FFmpegGlue* glue = FFmpegGlue::get();
+  FFmpegGlue* glue = FFmpegGlue::GetInstance();
 
   // Create our protocols and add them to the glue layer.
   scoped_ptr<StrictMock<Destroyable<MockProtocol> > > protocol_a(
@@ -144,7 +144,7 @@ TEST_F(FFmpegGlueTest, AddRemoveGetProtocol) {
 
 TEST_F(FFmpegGlueTest, OpenClose) {
   // Prepare testing data.
-  FFmpegGlue* glue = FFmpegGlue::get();
+  FFmpegGlue* glue = FFmpegGlue::GetInstance();
 
   // Create our protocol and add them to the glue layer.
   scoped_ptr<StrictMock<Destroyable<MockProtocol> > > protocol(
@@ -311,7 +311,7 @@ TEST_F(FFmpegGlueTest, Destroy) {
   // Create our protocol and add them to the glue layer.
   scoped_ptr<StrictMock<Destroyable<MockProtocol> > > protocol(
       new StrictMock<Destroyable<MockProtocol> >());
-  std::string key = FFmpegGlue::get()->AddProtocol(protocol.get());
+  std::string key = FFmpegGlue::GetInstance()->AddProtocol(protocol.get());
 
   // We should expect the protocol to get destroyed when the unit test
   // exits.