Disable Failing ios Chrome external url eg tests on device

These tests have been failing for more than a week now. LoadURL doesn't
finish on device on some tests.

Bug: 847948
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I151a3a2d031b4311d17c5c148c635a92e5a1f232
Reviewed-on: https://chromium-review.googlesource.com/1079630
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#562999}

ios/chrome/browser/metrics/external_url_tab_usage_recorder_egtest.mm

@@ -29,9 +29,15 @@ const char kTestUrl[] =
 
 @implementation ExternalURLTabUsageRecorderTestCase
 
+// TODO(crbug.com/847948): This test is faling on devices.
+#if TARGET_IPHONE_SIMULATOR
+#define MAYBE_testEvictedTabReloadFailure testEvictedTabReloadFailure
+#else
+#define MAYBE_testEvictedTabReloadFailure DISABLED_testEvictedTabReloadFailure
+#endif
 // Verify correct recording of metrics when the reloading of an evicted tab
 // fails.
-- (void)testEvictedTabReloadFailure {
+- (void)MAYBE_testEvictedTabReloadFailure {
   web::test::SetUpFileBasedHttpServer();
   chrome_test_util::HistogramTester histogramTester;
   FailureBlock failureBlock = ^(NSString* error) {

ios/chrome/browser/translate/translate_egtest.mm

@@ -471,8 +471,16 @@ using translate::LanguageDetectionController;
   [self assertLanguageDetails:expectedLanguageDetails];
 }
 
+// TODO(crbug.com/847948): This test is faling on devices.
+#if TARGET_IPHONE_SIMULATOR
+#define MAYBE_testLanguageDetectionHttpContentLanguage \
+  testLanguageDetectionHttpContentLanguage
+#else
+#define MAYBE_testLanguageDetectionHttpContentLanguage \
+  DISABLED_testLanguageDetectionHttpContentLanguage
+#endif
 // Tests that language in http content is detected.
-- (void)testLanguageDetectionHttpContentLanguage {
+- (void)MAYBE_testLanguageDetectionHttpContentLanguage {
   // Start the HTTP server.
   std::unique_ptr<web::DataResponseProvider> provider(new TestResponseProvider);
   web::test::SetUpHttpServer(std::move(provider));