Move QuicVersionManager into standalone .h/.cc. No behavior change.

net/quic/core/quic_protocol_test.cc

Index: net/quic/core/quic_protocol_test.cc
diff --git a/net/quic/core/quic_protocol_test.cc b/net/quic/core/quic_protocol_test.cc
index d9bacf5d2ecba6a799c72a751dee08789e240112..2ce81b62983f49504eb5b9c54bddecd1ded1090e 100644
--- a/net/quic/core/quic_protocol_test.cc
+++ b/net/quic/core/quic_protocol_test.cc
@@ -147,19 +147,6 @@ TEST(QuicProtocolTest, PathCloseFrameToString) {
   EXPECT_EQ("{ path_id: 1 }\n", stream.str());
 }
 
-TEST(QuicProtocolTest, QuicVersionManager) {
-  QuicFlagSaver flags;
-  FLAGS_quic_enable_version_36_v3 = false;
-  QuicVersionManager manager(AllSupportedVersions());
-  EXPECT_EQ(FilterSupportedVersions(AllSupportedVersions()),
-            manager.GetSupportedVersions());
-  FLAGS_quic_enable_version_36_v3 = true;
-  EXPECT_EQ(FilterSupportedVersions(AllSupportedVersions()),
-            manager.GetSupportedVersions());
-  EXPECT_EQ(QUIC_VERSION_36, manager.GetSupportedVersions()[0]);
-  EXPECT_EQ(QUIC_VERSION_35, manager.GetSupportedVersions()[1]);
-}
-
 // Tests that a queue contains the expected data after calls to Add().
 TEST(PacketNumberQueueTest, AddRange) {
   PacketNumberQueue queue;