NTLM: Always default NTLM to NTLMv2.

- This fixes that Android WebView did not default to NTLMv2
- This was changed already for all other platforms but it did not
  take effect on WebView.
- Sets the default value of ntlm_v2_enable_ to true in HttpAuthPreferences
- Previously the default was changed in flags, but it did not apply when
  a default HttpAuthPreferences was created, but no flags/features
  are overriden.

BUG=chromium:830542,chromium:22532
TEST=unittests

Change-Id: If660a9b5ab3a23735407468b30ee0f58aff5ce6c
Reviewed-on: https://chromium-review.googlesource.com/1030250
Commit-Queue: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Asanka Herath <asanka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#554873}

net/http/http_auth_handler_ntlm_portable_unittest.cc

@@ -31,6 +31,11 @@ class HttpAuthHandlerNtlmPortableTest : public PlatformTest {
   // Test input value defined in [MS-NLMP] Section 4.2.1.
   HttpAuthHandlerNtlmPortableTest() {
     http_auth_preferences_.reset(new MockAllowHttpAuthPreferences());
+    // Disable NTLMv2 for this end to end test because it's not possible
+    // to mock all the required dependencies for NTLMv2 from here. These
+    // tests are only of the overall flow, and the detailed tests of the
+    // contents of the protocol messages are in ntlm_client_unittest.cc
+    http_auth_preferences_->set_ntlm_v2_enabled(false);
     factory_.reset(new HttpAuthHandlerNTLM::Factory());
     factory_->set_http_auth_preferences(http_auth_preferences_.get());
     creds_ = AuthCredentials(

net/http/http_auth_preferences.cc

@@ -44,7 +44,7 @@ HttpAuthPreferences::HttpAuthPreferences(
       negotiate_disable_cname_lookup_(false),
       negotiate_enable_port_(false),
 #if defined(OS_POSIX)
-      ntlm_v2_enabled_(false),
+      ntlm_v2_enabled_(true),
 #endif
 #if defined(OS_CHROMEOS)
       allow_gssapi_library_load_(allow_gssapi_library_load),

net/http/http_auth_preferences_unittest.cc

@@ -41,11 +41,11 @@ TEST(HttpAuthPreferencesTest, NegotiateEnablePort) {
 }
 
 #if defined(OS_POSIX)
-TEST(HttpAuthPreferencesTest, EnableNtlmV2) {
+TEST(HttpAuthPreferencesTest, DisableNtlmV2) {
   HttpAuthPreferences http_auth_preferences;
-  EXPECT_FALSE(http_auth_preferences.NtlmV2Enabled());
-  http_auth_preferences.set_ntlm_v2_enabled(true);
   EXPECT_TRUE(http_auth_preferences.NtlmV2Enabled());
+  http_auth_preferences.set_ntlm_v2_enabled(false);
+  EXPECT_FALSE(http_auth_preferences.NtlmV2Enabled());
 }
 #endif