Fix SBER/PasswordProtectionServiceTest.VerifyContentTypeIsPopulated/0

This unit test currently waits for the timeout on network requests
to occur before it verifies the proper request was sent. This CL adds
a fake response so that the test runs quickly.

Bug: 899898
Change-Id: I9e35086647cc80344488abb3319a538e90785eb9
Reviewed-on: https://chromium-review.googlesource.com/c/1316411Reviewed-by: Varun Khaneja <vakh@chromium.org>
Commit-Queue: Varun Khaneja <vakh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605120}

components/safe_browsing/password_protection/password_protection_service_unittest.cc

@@ -1273,6 +1273,12 @@ TEST_P(PasswordProtectionServiceTest, VerifyIsEventLoggingEnabled) {
 }
 
 TEST_P(PasswordProtectionServiceTest, VerifyContentTypeIsPopulated) {
+  LoginReputationClientResponse response =
+      CreateVerdictProto(LoginReputationClientResponse::SAFE, 10 * kMinute,
+                         GURL(kTargetUrl).host());
+  test_url_loader_factory_.AddResponse(url_.spec(),
+                                       response.SerializeAsString());
+
   content::WebContents* web_contents = GetWebContents();
 
   content::WebContentsTester::For(web_contents)