SkyDemo should launch demos in their own windows

sky/sdk/example/demo_launcher/apk/AndroidManifest.xml

Index: sky/sdk/example/demo_launcher/apk/AndroidManifest.xml
diff --git a/sky/sdk/example/demo_launcher/apk/AndroidManifest.xml b/sky/sdk/example/demo_launcher/apk/AndroidManifest.xml
index 9d0ed17c8b85cc54aa9985a085f9b1f72e3c2647..037dd920adb4f57e7c1f508661ff07234018dff0 100644
--- a/sky/sdk/example/demo_launcher/apk/AndroidManifest.xml
+++ b/sky/sdk/example/demo_launcher/apk/AndroidManifest.xml
@@ -10,7 +10,12 @@
     <uses-feature android:name="android.hardware.sensor.accelerometer" android:required="true" />
 
     <application android:icon="@mipmap/ic_launcher" android:label="Sky" android:name="SkyDemoApplication">
-        <activity android:configChanges="orientation|keyboardHidden|keyboard|screenSize" android:hardwareAccelerated="true" android:name="SkyDemoActivity" android:theme="@android:style/Theme.Holo.Light.NoActionBar">
+        <activity android:name="SkyDemoActivity"
+                  android:launchMode="standard"
+                  android:documentLaunchMode="always"
+                  android:hardwareAccelerated="true"
+                  android:configChanges="orientation|keyboardHidden|keyboard|screenSize"
+                  android:theme="@android:style/Theme.Holo.Light.NoActionBar">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />