Enable all tests in CopylessPasteTest

chrome/android/javatests/src/org/chromium/chrome/browser/CopylessPasteTest.java

 // Copyright 2017 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.
 
 package org.chromium.chrome.browser;
 
 import android.support.test.filters.LargeTest;
 
 import org.chromium.base.Callback;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.base.test.util.CommandLineFlags;
-import org.chromium.base.test.util.DisabledTest;
 import org.chromium.base.test.util.Feature;
 import org.chromium.base.test.util.Restriction;
 import org.chromium.blink.mojom.document_metadata.Entity;
 import org.chromium.blink.mojom.document_metadata.Property;
 import org.chromium.blink.mojom.document_metadata.Values;
 import org.chromium.blink.mojom.document_metadata.WebPage;
 import org.chromium.chrome.browser.firstrun.FirstRunStatus;
 import org.chromium.chrome.test.ChromeTabbedActivityTestBase;
 import org.chromium.chrome.test.util.ChromeTabUtils;
 import org.chromium.net.test.EmbeddedTestServer;
@@ skipping 135 matching lines @@
         expected.entities = new Entity[1];
         expected.entities[0] = e;
         assertEquals(expected, extracted);
     }
 
     /**
      * Tests that CopylessPaste skips parsing visited pages.
      */
     @LargeTest
     @Feature({"CopylessPaste"})
-    @DisabledTest(message = "Flaky: crbug.com/713172")
     public void testCache() throws InterruptedException, TimeoutException {
-        // The URLs used here should be unique in CopylessPasteTest.
-        String uniqueTag = "#123";
-        // NODATA_PAGE doesn't contain desired metadata.
-        loadUrl(mTestServer.getURL(NODATA_PAGE + uniqueTag));
-        mCallbackHelper.waitForCallback(0);
-        // DATA_PAGE contains desired metadata.
-        loadUrl(mTestServer.getURL(DATA_PAGE + uniqueTag));
+        loadUrl(mTestServer.getURL(NODATA_PAGE));
+        loadUrl(mTestServer.getURL(DATA_PAGE));

[Maria, 2017/04/20 21:34:30]

From CL description, it sounds like you think that two waits are what's causing
flakiness (I find this a really odd explanation). But here you also remove the
unique tag from the test. Do you think that has an effect too?

I am a bit concerned that we are fixing the test by removing an expectation.

[wychen, 2017/04/20 22:00:54]

The flakiness of testNoMeta and testValid is around half of testCache, and all
the failures are about wait timeout, so I think this is the most reasonable
explanation.

It turned out that the uniqueTag is not needed since each test begins with a
clean cache. It shouldn't affect the flakiness.

The waits here are a bit redundant, since these expectations were checked in
other tests (testNoMeta and testValid respectively).
The cache-specific expectation is that repeated URLs don't get callback.
I keep one wait for readability.

         mCallbackHelper.waitForCallback(1);
 
         // Cache hit without entities. Shouldn't parse again.
-        loadUrl(mTestServer.getURL(NODATA_PAGE + uniqueTag));
+        loadUrl(mTestServer.getURL(NODATA_PAGE));
         // Cache hit with entities. Shouldn't parse again.
-        loadUrl(mTestServer.getURL(DATA_PAGE + uniqueTag));
+        loadUrl(mTestServer.getURL(DATA_PAGE));
         assertEquals(2, mCallbackHelper.getCallCount());
     }
 }