Improvements to QUIC client-side support of server push.

Increase test coverage.
  - Adds quic_client_push_promise_index_test

API cleanups
  - replace unique_ptr params with const &
  - expunge QuicSpdyStream::Visitor from push promise classes, move small bit
    of related logic to quic*client.
  - rename OnResponse() to OnRendezvousResult()
Other
  - Check IsClosed() earlier in Try(), so client will not hang in rendezvous (until cleanup alarm fires)  if the data stream was reset before the corresponding response headers arrived.
  - remove dead instance of |DataToResend|

Merge internal change: 113642684

BUG=

Review URL: https://codereview.chromium.org/1661083003

Cr-Commit-Position: refs/heads/master@{#373627}
diff --git a/net/net.gypi b/net/net.gypi
index a7f1dc1..52f5735 100644
--- a/net/net.gypi
+++ b/net/net.gypi
@@ -1576,6 +1576,7 @@
       'quic/quic_chromium_client_session_test.cc',
       'quic/quic_chromium_client_stream_test.cc',
       'quic/quic_chromium_connection_helper_test.cc',
+      'quic/quic_client_push_promise_index_test.cc',
       'quic/quic_clock_test.cc',
       'quic/quic_config_test.cc',
       'quic/quic_connection_logger_unittest.cc',
@@ -1629,6 +1630,8 @@
       'quic/test_tools/mock_crypto_client_stream.h',
       'quic/test_tools/mock_crypto_client_stream_factory.cc',
       'quic/test_tools/mock_crypto_client_stream_factory.h',
+      'quic/test_tools/mock_quic_client_promised_info.cc',
+      'quic/test_tools/mock_quic_client_promised_info.h',
       'quic/test_tools/mock_quic_dispatcher.cc',
       'quic/test_tools/mock_quic_dispatcher.h',
       'quic/test_tools/mock_quic_spdy_client_stream.cc',