Propagate error messages to UI for blimp.

chrome/android/javatests/src/org/chromium/chrome/browser/blimp/BlimpMessageBuilderTest.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/blimp/BlimpMessageBuilderTest.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/blimp/BlimpMessageBuilderTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/blimp/BlimpMessageBuilderTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..6c711eda4c1cd3c100f11537b32e47219e01196f
--- /dev/null
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/blimp/BlimpMessageBuilderTest.java
@@ -0,0 +1,71 @@
+// Copyright 2016 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.blimp;
+
+import android.app.Activity;
+import android.test.suitebuilder.annotation.MediumTest;
+
+import org.chromium.base.ApplicationStatus;
+import org.chromium.base.ThreadUtils;
+import org.chromium.chrome.browser.blimp.ui.BlimpMessageBuilder;
+import org.chromium.chrome.browser.snackbar.Snackbar;
+import org.chromium.chrome.browser.snackbar.SnackbarManager;
+import org.chromium.chrome.test.ChromeTabbedActivityTestBase;
+import org.chromium.content.browser.test.util.Criteria;
+import org.chromium.content.browser.test.util.CriteriaHelper;
+
+/**
+ * Test BlimpMessageBuilder.
+ */
+public class BlimpMessageBuilderTest extends ChromeTabbedActivityTestBase {
+    private static final String TEST_MSG = "Snackbar show, snackbar.";
+    private SnackbarManager mManager;
+
+    @Override
+    public void startMainActivity() throws InterruptedException {
+        startMainActivityOnBlankPage();
+        mManager = getActivity().getSnackbarManager();
+    }
+
+    private static class MockBlimpMessageBuilder extends BlimpMessageBuilder {
+        Snackbar getSnackbar() {
+            return super.getSnackbarForTest();
+        }
+
+        // Override this method to expose visibility for this test.
+        @Override
+        public SnackbarManager getSnackbarManager(Activity activity) {
+            return super.getSnackbarManager(activity);
+        }
+    }
+
+    /**
+     * Test if we can show {@link Snackbar} in ChromeTabbedActivity.
+     */
+    @MediumTest
+    public void testSnackbarMessage() throws Exception {
+        final MockBlimpMessageBuilder mockBuilder = new MockBlimpMessageBuilder();
+        Activity activity = ApplicationStatus.getLastTrackedFocusedActivity();
+        assertTrue(activity instanceof SnackbarManager.SnackbarManageable);
+        assertNotNull(mockBuilder.getSnackbarManager(activity));
+
+        ThreadUtils.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                mockBuilder.showMessage(TEST_MSG);
+                assertNotNull("Builder should hold a snackbar.", mockBuilder.getSnackbar());
+            }
+        });
+
+        // Wait for the {@link Snackbar} to show within default timeout of {@link CriteriaHelper}.
+        CriteriaHelper.pollUiThread(new Criteria("Snackbar should show.") {
+            @Override
+            public boolean isSatisfied() {
+                return mManager.isShowing()
+                        && (mManager.getCurrentSnackbarForTesting() == mockBuilder.getSnackbar());
+            }
+        });
+    }
+}