Add a --checked argument to sky_tool start

The --checked argument runs SkyShell in checked mode, which turns on type
checking and asserts.

sky/packages/sky/lib/sky_tool

@@ -127,6 +127,7 @@ class StartSky(object):
             help='launch %s on the device' % APK_NAME)
         start_parser.add_argument('--install', action='store_true')
         start_parser.add_argument('--poke', action='store_true')
+        start_parser.add_argument('--checked', action='store_true')
         start_parser.add_argument('project_or_path', nargs='?', type=str,
             default='.')
         start_parser.set_defaults(func=self.run)
@@ -212,11 +213,19 @@ class StartSky(object):
         if args.poke:
             url += '?rand=%s' % random.random()
 
-        subprocess.check_call([ADB_PATH, 'shell',
+        cmd = [
+            ADB_PATH, 'shell',
             'am', 'start',
             '-a', 'android.intent.action.VIEW',
             '-d', url,
-            ANDROID_COMPONENT])
+        ]
+
+        if args.checked:
+            cmd += [ '--ez', 'enable-checked-mode', 'true' ]
+
+        cmd += [ ANDROID_COMPONENT ]
+        print cmd
+        subprocess.check_call(cmd)
 
 
 class StopSky(object):

sky/shell/android/org/domokit/sky/shell/SkyActivity.java

@@ -26,6 +26,17 @@ public class SkyActivity extends Activity {
     private TracingController mTracingController;
     private PlatformViewAndroid mView;
 
+    private String[] getArgsFromIntent(Intent intent) {
+        // Before adding more entries to this list, consider that arbitrary
+        // Android applications can generate intents with extra data and that
+        // there are many security-sensitive args in the binary.
+        if (intent.getBooleanExtra("enable-checked-mode", false)) {
+            String[] args = { "--enable-checked-mode"};
+            return args;
+        }
+        return null;
+    }
+
     /**
      * @see android.app.Activity#onCreate(android.os.Bundle)
      */
@@ -47,7 +58,8 @@ public class SkyActivity extends Activity {
                 View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                 | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
 
-        SkyMain.ensureInitialized(getApplicationContext());
+        String[] args = getArgsFromIntent(getIntent());
+        SkyMain.ensureInitialized(getApplicationContext(), args);
         mView = new PlatformViewAndroid(this, edgeDims);
         ActivityImpl.setCurrentActivity(this);
         setContentView(mView);

sky/shell/android/org/domokit/sky/shell/SkyMain.java

@@ -25,14 +25,14 @@ public class SkyMain {
     /**
      * Initializes the native system.
      **/
-    public static void ensureInitialized(Context applicationContext) {
+    public static void ensureInitialized(Context applicationContext, String[] args) {
         if (sInitialized) {
             return;
         }
         try {
             SkyApplication app = (SkyApplication) applicationContext;
             app.getResourceExtractor().waitForCompletion();
-            nativeInit(applicationContext);
+            nativeInit(applicationContext, args);
             // Create the mojo run loop.
             CoreImpl.getInstance().createDefaultRunLoop();
             sInitialized = true;
@@ -42,5 +42,5 @@ public class SkyMain {
         }
     }
 
-    private static native void nativeInit(Context context);
+    private static native void nativeInit(Context context, String[] args);
 }

sky/shell/android/sky_main.cc

@@ -43,11 +43,20 @@ void InitializeLogging() {
 
 }  // namespace
 
-static void Init(JNIEnv* env, jclass clazz, jobject context) {
+static void Init(JNIEnv* env,
+                 jclass clazz,
+                 jobject context,
+                 jobjectArray jargs) {
   base::android::ScopedJavaLocalRef<jobject> scoped_context(env, context);
   base::android::InitApplicationContext(env, scoped_context);
 
+  std::vector<std::string> args;
+  args.push_back("sky_shell");
+  base::android::AppendJavaStringArrayToStringVector(env, jargs, &args);
+
   base::CommandLine::Init(0, nullptr);
+  base::CommandLine::ForCurrentProcess()->InitFromArgv(args);
+
   InitializeLogging();
 
   g_java_message_loop.Get().reset(new base::MessageLoopForUI);

sky/shell/ui/engine.cc

@@ -87,13 +87,13 @@ base::WeakPtr<Engine> Engine::GetWeakPtr() {
 void Engine::Init() {
   TRACE_EVENT0("sky", "Engine::Init");
 
-  DCHECK(!g_platform_impl);
-  g_platform_impl = new PlatformImpl();
-  blink::initialize(g_platform_impl);
-
   base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
   blink::WebRuntimeFeatures::enableDartCheckedMode(
       command_line.HasSwitch(switches::kEnableCheckedMode));
+
+  DCHECK(!g_platform_impl);
+  g_platform_impl = new PlatformImpl();
+  blink::initialize(g_platform_impl);
 }
 
 void Engine::BeginFrame(base::TimeTicks frame_time) {