Fix flakiness in ChromeBrowserInitializerTest

Allow disk reads so the test running handleSynchronousStartup() does not
trigger strict mode violations.

Bug: 1131373
Change-Id: If3e0ccd0fa51c7f6a492bcf7793b40ee88e84d2e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2441649Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812393}

chrome/android/javatests/src/org/chromium/chrome/browser/init/ChromeBrowserInitializerTest.java

@@ -11,7 +11,7 @@ import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
-import org.chromium.base.test.util.DisabledTest;
+import org.chromium.base.StrictModeContext;
 import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.content_public.browser.test.util.TestThreadUtils;
 
@@ -31,11 +31,12 @@ public class ChromeBrowserInitializerTest {
 
     @Test
     @SmallTest
-    @DisabledTest(message = "https://crbug.com/1131373")
     public void testSynchronousInitialization() throws Exception {
         TestThreadUtils.runOnUiThreadBlocking(() -> {
             Assert.assertFalse(mInstance.isFullBrowserInitialized());
-            mInstance.handleSynchronousStartup();
+            try (StrictModeContext ignored = StrictModeContext.allowDiskReads()) {
+                mInstance.handleSynchronousStartup();
+            }
             Assert.assertTrue(mInstance.isFullBrowserInitialized());
             return true;
         });
@@ -73,7 +74,9 @@ public class ChromeBrowserInitializerTest {
         TestThreadUtils.runOnUiThreadBlocking(() -> {
             mInstance.runNowOrAfterFullBrowserStarted(done::release);
             Assert.assertFalse("Should not run synchronously", done.tryAcquire());
-            mInstance.handleSynchronousStartup();
+            try (StrictModeContext ignored = StrictModeContext.allowDiskReads()) {
+                mInstance.handleSynchronousStartup();
+            }
             Assert.assertTrue(done.tryAcquire());
             return true;
         });