Third try at landing gRPC refactoring. Previous issue failed on the waterfall

components/cronet/ios/Cronet.mm

Index: components/cronet/ios/Cronet.mm
diff --git a/components/cronet/ios/Cronet.mm b/components/cronet/ios/Cronet.mm
index 150be2435ff32b9919574f60c8766995eb4f698b..d413f97de704039f29790589dff8d5ff0b7e70d9 100644
--- a/components/cronet/ios/Cronet.mm
+++ b/components/cronet/ios/Cronet.mm
@@ -41,7 +41,6 @@ RequestFilterBlock gRequestFilterBlock = nil;
 std::unique_ptr<CronetHttpProtocolHandlerDelegate> gHttpProtocolHandlerDelegate;
 NSURLCache* gPreservedSharedURLCache = nil;
 BOOL gEnableTestCertVerifierForTesting = FALSE;
-NSString* gHostResolverRulesForTesting = @"";
 
 // CertVerifier, which allows any certificates for testing.
 class TestCertVerifier : public net::CertVerifier {
@@ -106,8 +105,6 @@ class CronetHttpProtocolHandlerDelegate
 
 + (void)configureCronetEnvironmentForTesting:
     (cronet::CronetEnvironment*)cronetEnvironment {
-  cronetEnvironment->set_host_resolver_rules(
-      [gHostResolverRulesForTesting UTF8String]);
   if (gEnableTestCertVerifierForTesting) {
     std::unique_ptr<TestCertVerifier> test_cert_verifier =
         base::MakeUnique<TestCertVerifier>();
@@ -254,11 +251,11 @@ class CronetHttpProtocolHandlerDelegate
                             encoding:[NSString defaultCStringEncoding]];
 }
 
-+ (cronet_engine*)getGlobalEngine {
++ (stream_engine*)getGlobalEngine {
   DCHECK(gChromeNet.Get().get());
   if (gChromeNet.Get().get()) {
-    static cronet_engine engine;
-    engine.obj = gChromeNet.Get().get();
+    static stream_engine engine;
+    engine.obj = gChromeNet.Get()->GetURLRequestContextGetter();
     return &engine;
   }
   return nil;
@@ -277,13 +274,15 @@ class CronetHttpProtocolHandlerDelegate
 }
 
 + (void)setHostResolverRulesForTesting:(NSString*)hostResolverRulesForTesting {
-  gHostResolverRulesForTesting = hostResolverRulesForTesting;
+  DCHECK(gChromeNet.Get().get());
+  gChromeNet.Get()->SetHostResolverRules(
+      base::SysNSStringToUTF8(hostResolverRulesForTesting));
 }
 
 // This is a non-public dummy method that prevents the linker from stripping out
-// the otherwise non-referenced methods from 'cronet_bidirectional_stream.cc'.
+// the otherwise non-referenced methods from 'bidirectional_stream.cc'.
 + (void)preventStrippingCronetBidirectionalStream {
-  cronet_bidirectional_stream_create(NULL, 0, 0);
+  bidirectional_stream_create(NULL, 0, 0);
 }
 
 @end