Remove unused HostResolver::Observer.

net/http/http_network_transaction_unittest.cc

Index: net/http/http_network_transaction_unittest.cc
diff --git a/net/http/http_network_transaction_unittest.cc b/net/http/http_network_transaction_unittest.cc
index 7c02e83e8b5501b3d3c3b67dd5091730ff010839..92e20c0e5dea41d4d5fdc4e8f72039e76ad95edb 100644
--- a/net/http/http_network_transaction_unittest.cc
+++ b/net/http/http_network_transaction_unittest.cc
@@ -5794,31 +5794,41 @@ TEST_F(HttpNetworkTransactionTest, ReconsiderProxyAfterFailedConnection) {
   EXPECT_EQ(ERR_PROXY_CONNECTION_FAILED, rv);
 }
 
-// Host resolution observer used by
-// HttpNetworkTransactionTest.ResolveMadeWithReferrer to check that host
-// resovle requests are issued with a referrer of |expected_referrer|.
-class ResolutionReferrerObserver : public HostResolver::Observer {
+// Forwards all calls to MockHostResolverBase but notes RequestInfo::referrer().
+// Used by HttpNetworkTransactionTest.ResolveMadeWithReferrer to check that host
+// resolve requests are issued with a referrer of |expected_referrer|.
+class ObservingHostResolver : public MockHostResolverBase {
  public:
-  explicit ResolutionReferrerObserver(const GURL& expected_referrer)
-      : expected_referrer_(expected_referrer),
+  explicit ObservingHostResolver(const GURL& expected_referrer)
+      : MockHostResolverBase(false /* use_caching */),
+        expected_referrer_(expected_referrer),
         called_start_with_referrer_(false),
-        called_finish_with_referrer_(false) {
+        called_finish_with_referrer_(false),
+        ALLOW_THIS_IN_INITIALIZER_LIST(
+            callback_(this,
+                      &ObservingHostResolver::OnFinishResolutionWithStatus)) {
   }
 
-  virtual void OnStartResolution(int id,
-                                 const HostResolver::RequestInfo& info) {
-    if (info.referrer() == expected_referrer_)
+  virtual int Resolve(const RequestInfo& info,
+                      AddressList* addresses,
+                      OldCompletionCallback* callback,
+                      RequestHandle* out_req,
+                      const BoundNetLog& net_log) OVERRIDE {
+    if (info.referrer() == expected_referrer_) {
       called_start_with_referrer_ = true;
+      callback_forwarded_ = callback;
+      callback = &callback_;
+    }
+    return MockHostResolverBase::Resolve(info, addresses, callback, out_req,
+                                         net_log);
   }
 
-  virtual void OnFinishResolutionWithStatus(
-      int id, bool was_resolved, const HostResolver::RequestInfo& info ) {
-    if (info.referrer() == expected_referrer_)
-      called_finish_with_referrer_ = true;
+  void OnFinishResolutionWithStatus(int result) {
+    called_finish_with_referrer_ = true;
+    callback_forwarded_->Run(result);
   }
 
-  virtual void OnCancelResolution(int id,
-                                  const HostResolver::RequestInfo& info ) {
+  virtual void CancelRequest(RequestHandle handle) OVERRIDE {
     FAIL() << "Should not be cancelling any requests!";
   }
 
@@ -5830,8 +5840,10 @@ class ResolutionReferrerObserver : public HostResolver::Observer {
   GURL expected_referrer_;
   bool called_start_with_referrer_;
   bool called_finish_with_referrer_;
+  OldCompletionCallbackImpl<ObservingHostResolver> callback_;
+  OldCompletionCallback* callback_forwarded_;
 
-  DISALLOW_COPY_AND_ASSIGN(ResolutionReferrerObserver);
+  DISALLOW_COPY_AND_ASSIGN(ObservingHostResolver);
 };
 
 // Make sure that when HostResolver::Resolve() is invoked, it passes through
@@ -5839,7 +5851,6 @@ class ResolutionReferrerObserver : public HostResolver::Observer {
 TEST_F(HttpNetworkTransactionTest, ResolveMadeWithReferrer) {
   GURL referrer = GURL("http://expected-referrer/");
   EXPECT_TRUE(referrer.is_valid());
-  ResolutionReferrerObserver resolution_observer(referrer);
 
   // Issue a request, containing an HTTP referrer.
   HttpRequestInfo request;
@@ -5849,12 +5860,14 @@ TEST_F(HttpNetworkTransactionTest, ResolveMadeWithReferrer) {
                                   referrer.spec());
 
   SessionDependencies session_deps;
+  // Attach an observer to watch the host resolutions being made.
+  ObservingHostResolver* observing_resolver =
+      new ObservingHostResolver(referrer);
+  session_deps.host_resolver.reset(observing_resolver);
+
   scoped_ptr<HttpTransaction> trans(new HttpNetworkTransaction(
       CreateSession(&session_deps)));
 
-  // Attach an observer to watch the host resolutions being made.
-  session_deps.host_resolver->AddObserver(&resolution_observer);
-
   // Connect up a mock socket which will fail when reading.
   MockRead data_reads[] = {
     MockRead(false, ERR_FAILED),
@@ -5870,7 +5883,7 @@ TEST_F(HttpNetworkTransactionTest, ResolveMadeWithReferrer) {
   EXPECT_EQ(ERR_FAILED, rv);
 
   // Check that the host resolution observer saw |referrer|.
-  EXPECT_TRUE(resolution_observer.did_complete_with_expected_referrer());
+  EXPECT_TRUE(observing_resolver->did_complete_with_expected_referrer());
 }
 
 // Base test to make sure that when the load flags for a request specify to
@@ -9139,14 +9152,6 @@ class OneTimeCachingHostResolver : public net::HostResolver {
     host_resolver_.CancelRequest(req);
   }
 
-  virtual void AddObserver(Observer* observer) OVERRIDE {
-    return host_resolver_.AddObserver(observer);
-  }
-
-  virtual void RemoveObserver(Observer* observer) OVERRIDE {
-    return host_resolver_.RemoveObserver(observer);
-  }
-
   MockCachingHostResolver* GetMockHostResolver() {
     return &host_resolver_;
   }