Add integration tests for WebAPKs

chrome/android/java/AndroidManifest.xml

Index: chrome/android/java/AndroidManifest.xml
diff --git a/chrome/android/java/AndroidManifest.xml b/chrome/android/java/AndroidManifest.xml
index b5b9a97aa9c4db1357f2f7c05663ec170e94cbf3..1f74a34309f5f2ef6dc9c345c61e7a6960467e36 100644
--- a/chrome/android/java/AndroidManifest.xml
+++ b/chrome/android/java/AndroidManifest.xml
@@ -937,6 +937,17 @@ android:value="true" />
         <meta-data android:name="org.chromium.content.browser.REMOTE_MEDIA_PLAYERS"
             android:value="org.chromium.chrome.browser.media.remote.DefaultMediaRouteController"/>
 
-        {% endblock %}
+          {% endblock %}
+
+        <activity android:name="org.chromium.chrome.browser.webapps.TestWebApkActivity"

[gone, 2017/02/21 22:31:50]

Eh, I am strongly against adding a test-specific Activity to the real manifest
-- we'll never be able to remove it.  Will it work if it's in
chrome/android/javatests/AndroidManifest.xml instead?

[pkotwicz, 2017/02/24 23:49:55]

That's what I meant to do. Thank you very much for catching!

I ended up removing TestWebApkActivity. Instrumentation#startActivitySync() does
not like activities defined in the test application (instead of defined in the
application under test) I have now added a static method
WebApkUpdateManager#setUpdatesEnabledForTesting()

+            android:theme="@style/WebappTheme"
+            android:label="@string/webapp_activity_title"
+            android:launchMode="singleTop"
+            android:documentLaunchMode="intoExisting"
+            android:windowSoftInputMode="adjustResize"
+            android:persistableMode="persistNever"
+            android:hardwareAccelerated="false"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|mcc|mnc|screenLayout|smallestScreenSize">
+        </activity>
     </application>
 </manifest>