WebLayer: rewrite testOnRenderProcessGone

I couldn't reproduce or understand the flakiness, but hopefully
rewriting the test to use TestWebLayer#crashTab instead of
navigating to chrome://crash will resolve the problem.

FWIW, in the old version of the test, the navigation itself
seemed to fail, in that the post-test screenshot still showed
about:blank in the url bar.

Bug: 1143788
Change-Id: I35cbca4368f7215fd173692c1d2a24ed34fe8e4e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2535218Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827385}

weblayer/browser/android/javatests/src/org/chromium/weblayer/test/TabCallbackTest.java

@@ -84,26 +84,6 @@ public class TabCallbackTest {
         callback.visibleUriChangedCallback.waitUntilValueObserved(url);
     }
 
-    @Test
-    @SmallTest
-    public void testOnRenderProcessGone() throws TimeoutException {
-        InstrumentationActivity activity = mActivityTestRule.launchShellWithUrl("about:blank");
-        CallbackHelper callbackHelper = new CallbackHelper();
-        TestThreadUtils.runOnUiThreadBlocking(() -> {
-            Tab tab = activity.getTab();
-            activity.setIgnoreRendererCrashes();
-            TabCallback callback = new TabCallback() {
-                @Override
-                public void onRenderProcessGone() {
-                    callbackHelper.notifyCalled();
-                }
-            };
-            tab.registerTabCallback(callback);
-            tab.getNavigationController().navigate(Uri.parse("chrome://crash"));
-        });
-        callbackHelper.waitForFirst();
-    }
-
     // Requires implementation M82.
     @Test
     @SmallTest

weblayer/browser/android/javatests/src/org/chromium/weblayer/test/TabPrivateTest.java

@@ -95,4 +95,25 @@ public class TabPrivateTest {
         });
         navigationCompletedHelper.waitForFirst();
     }
+
+    @Test
+    @SmallTest
+    public void testOnRenderProcessGone() throws Exception {
+        InstrumentationActivity activity = mActivityTestRule.launchShellWithUrl("about:blank");
+        CallbackHelper callbackHelper = new CallbackHelper();
+        Tab tabToCrash = TestThreadUtils.runOnUiThreadBlocking(() -> {
+            Tab tab = activity.getTab();
+            activity.setIgnoreRendererCrashes();
+            TabCallback callback = new TabCallback() {
+                @Override
+                public void onRenderProcessGone() {
+                    callbackHelper.notifyCalled();
+                }
+            };
+            tab.registerTabCallback(callback);
+            return tab;
+        });
+        getTestWebLayer().crashTab(tabToCrash);
+        callbackHelper.waitForFirst();
+    }
 }