Create ChromeEarlGrey waitForWebViewContainingText.

ios/chrome/browser/ui/browser_view_controller_egtest.mm

Index: ios/chrome/browser/ui/browser_view_controller_egtest.mm
diff --git a/ios/chrome/browser/ui/browser_view_controller_egtest.mm b/ios/chrome/browser/ui/browser_view_controller_egtest.mm
index b6445ba16e9f171439395a52990783722de0186f..51afc521d0db3a34d7f2c42333cb1e3f99d0c715 100644
--- a/ios/chrome/browser/ui/browser_view_controller_egtest.mm
+++ b/ios/chrome/browser/ui/browser_view_controller_egtest.mm
@@ -53,10 +53,7 @@
   [ChromeEarlGrey loadURL:startURL];
 
   // Waits for the page to load and check it is the expected content.
-  id<GREYMatcher> responseMatcher =
-      chrome_test_util::WebViewContainingText(responses[startURL]);
-  [[EarlGrey selectElementWithMatcher:responseMatcher]
-      assertWithMatcher:grey_notNil()];
+  [ChromeEarlGrey waitForWebViewContainingText:responses[startURL]];
 
   // In the omnibox, the URL should be present, without the http:// prefix.
   [[EarlGrey selectElementWithMatcher:chrome_test_util::Omnibox()]
@@ -81,10 +78,7 @@
                   @"Did not navigate to the destination url.");
 
   // Verifies that the destination page is shown.
-  id<GREYMatcher> navigationMatcher =
-      chrome_test_util::WebViewContainingText(responses[destinationURL]);
-  [[EarlGrey selectElementWithMatcher:grey_kindOfClass([WKWebView class])]
-      assertWithMatcher:navigationMatcher];
+  [ChromeEarlGrey waitForWebViewContainingText:responses[destinationURL]];
 }
 
 @end