Throttle HttpStreamFactoryImpl::Job to HTTP/2-supported servers

net/spdy/chromium/spdy_session_pool.cc

Index: net/spdy/chromium/spdy_session_pool.cc
diff --git a/net/spdy/chromium/spdy_session_pool.cc b/net/spdy/chromium/spdy_session_pool.cc
index 80511f2d1a706ab772ddce29dcc21615d1884990..1313be616b959bdd02f42cccab3726fbc8211fe6 100644
--- a/net/spdy/chromium/spdy_session_pool.cc
+++ b/net/spdy/chromium/spdy_session_pool.cc
@@ -438,6 +438,41 @@ void SpdySessionPool::OnNewSpdySessionReady(
   // TODO(mbelshe): Alert other valid requests.
 }
 
+bool SpdySessionPool::StartRequest(const SpdySessionKey& spdy_session_key,
+                                   const base::Closure& callback) {
+  auto iter = spdy_session_pending_request_map_.find(spdy_session_key);
+  if (iter == spdy_session_pending_request_map_.end()) {
+    spdy_session_pending_request_map_.emplace(spdy_session_key,
+                                              std::list<base::Closure>{});
+    return true;
+  }
+  iter->second.push_back(callback);
+  return false;
+}
+
+void SpdySessionPool::ResumeAllPendingRequests(
+    const SpdySessionKey& spdy_session_key) {
+  auto iter = spdy_session_pending_request_map_.find(spdy_session_key);
+  if (iter != spdy_session_pending_request_map_.end()) {
+    for (auto callback : iter->second) {
+      base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, callback);
+    }
+    spdy_session_pending_request_map_.erase(iter);
+  }
+}
+
+void SpdySessionPool::ResumeNextPendingRequest(
+    const SpdySessionKey& spdy_session_key) {
+  auto iter = spdy_session_pending_request_map_.find(spdy_session_key);
+  if (iter != spdy_session_pending_request_map_.end()) {
+    base::Closure callback = iter->second.front();
+    if (iter->second.size() == 1)
+      spdy_session_pending_request_map_.erase(iter);
+    iter->second.pop_front();

[Bence, 2017/06/09 19:17:39]

Do not dereference |iter| after it's erased.  How about:

base::Closure callback = iter->second.front();
iter->second.pop_front();
if (iter->second.empty())
  spdy_session_pending_request_map_.erase(iter);

[xunjieli, 2017/06/13 15:23:11]

Done. Thanks!

+    base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, callback);
+  }
+}
+
 void SpdySessionPool::AddRequestToSpdySessionRequestMap(
     const SpdySessionKey& spdy_session_key,
     HttpStreamFactoryImpl::Request* request) {
@@ -462,6 +497,7 @@ void SpdySessionPool::RemoveRequestFromSpdySessionRequestMap(
   if (request_set.empty())
     spdy_session_request_map_.erase(spdy_session_key);
   request->ResetSpdySessionKey();
+  ResumeNextPendingRequest(spdy_session_key);
 }
 
 void SpdySessionPool::DumpMemoryStats(