Disabled three flaky cronet tests.

components/cronet/stale_host_resolver_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/cronet/stale_host_resolver.h"
 
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
@@ skipping 423 matching lines @@
     EXPECT_EQ(1u, resolve_addresses().size()) << i;
     {
       const char* expected = test_case.usable ? kCacheAddress : kNetworkAddress;
       EXPECT_EQ(expected, resolve_addresses()[0].ToStringWithoutPort()) << i;
     }
 
     DestroyResolver();
   }
 }
 
-TEST_F(StaleHostResolverTest, CreatedByContext) {
+// Test is flaky. See https://crbug.com/737326.
+TEST_F(StaleHostResolverTest, DISABLED_CreatedByContext) {
   URLRequestContextConfig config(
       // Enable QUIC.
       true,
       // QUIC User Agent ID.
       "Default QUIC User Agent ID",
       // Enable SPDY.
       true,
       // Enable SDCH.
       false,
       // Enable Brotli.
@@ skipping 44 matching lines @@
 
   EXPECT_TRUE(resolve_complete());
   EXPECT_EQ(net::OK, resolve_error());
   EXPECT_EQ(1u, resolve_addresses().size());
   EXPECT_EQ(kCacheAddress, resolve_addresses()[0].ToStringWithoutPort());
 }
 
 }  // namespace
 
 }  // namespace cronet