Server push cancellation: add PushPromiseHelper which reflects information on the push promise.

net/quic/chromium/quic_chromium_client_session.cc

Index: net/quic/chromium/quic_chromium_client_session.cc
diff --git a/net/quic/chromium/quic_chromium_client_session.cc b/net/quic/chromium/quic_chromium_client_session.cc
index 72fab95b2afcbfa5ccf40224efec042b2cd9cff1..ea08e694e8ee95ad2f623f7cc86d84eb6e0777fb 100644
--- a/net/quic/chromium/quic_chromium_client_session.cc
+++ b/net/quic/chromium/quic_chromium_client_session.cc
@@ -31,6 +31,7 @@
 #include "net/quic/core/quic_client_promised_info.h"
 #include "net/quic/core/quic_crypto_client_stream_factory.h"
 #include "net/quic/core/spdy_utils.h"
+#include "net/spdy/spdy_http_utils.h"
 #include "net/spdy/spdy_session.h"
 #include "net/ssl/channel_id_service.h"
 #include "net/ssl/ssl_connection_status_flags.h"
@@ -162,6 +163,26 @@ class HpackDecoderDebugVisitor : public QuicHeadersStream::HpackDebugVisitor {
   }
 };
 
+class QuicPushPromiseHelper : public PushPromiseHelper {
+ public:
+  explicit QuicPushPromiseHelper(
+      base::WeakPtr<QuicChromiumClientSession> session,
+      const GURL& url)
+      : session_(session), request_url_(url) {}
+
+  void Cancel() override {
+    if (session_) {
+      session_->CancelPush(request_url_);
+    }
+  }
+
+  const GURL& GetURL() override { return request_url_; }
+
+ private:
+  base::WeakPtr<QuicChromiumClientSession> session_;
+  const GURL request_url_;
+};
+
 }  // namespace
 
 QuicChromiumClientSession::StreamRequest::StreamRequest() : stream_(nullptr) {}
@@ -242,6 +263,7 @@ QuicChromiumClientSession::QuicChromiumClientSession(
       going_away_(false),
       port_migration_detected_(false),
       token_binding_signatures_(kTokenBindingSignatureMapSize),
+      push_delegate_(nullptr),
       streams_pushed_count_(0),
       streams_pushed_and_claimed_count_(0),
       bytes_pushed_count_(0),
@@ -1412,13 +1434,23 @@ bool QuicChromiumClientSession::HasNonMigratableStreams() const {
   return false;
 }
 
-void QuicChromiumClientSession::HandlePromised(QuicStreamId id,
+bool QuicChromiumClientSession::HandlePromised(QuicStreamId id,
                                                QuicStreamId promised_id,
                                                const SpdyHeaderBlock& headers) {
-  QuicClientSessionBase::HandlePromised(id, promised_id, headers);
+  bool result = QuicClientSessionBase::HandlePromised(id, promised_id, headers);
+  if (result) {
+    // The push promise is accepted, notify the push_delegate that a push
+    // promise has been received.
+    GURL pushed_url = GetUrlFromHeaderBlock(headers);
+    if (push_delegate_) {
+      push_delegate_->OnPush(base::MakeUnique<QuicPushPromiseHelper>(
+          weak_factory_.GetWeakPtr(), pushed_url));
+    }
+  }
   net_log_.AddEvent(NetLogEventType::QUIC_SESSION_PUSH_PROMISE_RECEIVED,
                     base::Bind(&NetLogQuicPushPromiseReceivedCallback, &headers,
                                id, promised_id));
+  return result;
 }
 
 void QuicChromiumClientSession::DeletePromised(