Create abstract interface for media::Pipeline.

media/test/pipeline_integration_test.cc

Index: media/test/pipeline_integration_test.cc
diff --git a/media/test/pipeline_integration_test.cc b/media/test/pipeline_integration_test.cc
index 43da5c1d69ea4d6f97f6e728ca385208fa451605..1f2a2311c1cf9a136de480cf3f7aa6144a33bed0 100644
--- a/media/test/pipeline_integration_test.cc
+++ b/media/test/pipeline_integration_test.cc
@@ -695,8 +695,9 @@ class PipelineIntegrationTest : public PipelineIntegrationTestHost {
     EXPECT_CALL(*this, OnWaitingForDecryptionKey()).Times(0);
 
     demuxer_ = source->GetDemuxer();
+    scoped_ptr<Renderer> renderer = CreateRenderer();
     pipeline_->Start(
-        demuxer_.get(), CreateRenderer(),
+        demuxer_.get(), &renderer,
         base::Bind(&PipelineIntegrationTest::OnEnded, base::Unretained(this)),
         base::Bind(&PipelineIntegrationTest::OnError, base::Unretained(this)),
         base::Bind(&PipelineIntegrationTest::OnStatusCallback,
@@ -742,13 +743,14 @@ class PipelineIntegrationTest : public PipelineIntegrationTestHost {
     EXPECT_CALL(*this, OnWaitingForDecryptionKey()).Times(0);
 
     demuxer_ = source->GetDemuxer();
+    scoped_ptr<Renderer> renderer = CreateRenderer();
 
     pipeline_->SetCdm(encrypted_media->GetCdmContext(),
                       base::Bind(&PipelineIntegrationTest::DecryptorAttached,
                                  base::Unretained(this)));
 
     pipeline_->Start(
-        demuxer_.get(), CreateRenderer(),
+        demuxer_.get(), &renderer,
         base::Bind(&PipelineIntegrationTest::OnEnded, base::Unretained(this)),
         base::Bind(&PipelineIntegrationTest::OnError, base::Unretained(this)),
         base::Bind(&PipelineIntegrationTest::OnStatusCallback,