Add support for webapk without runtimeHost

chrome/android/webapk/shell_apk/src/org/chromium/webapk/shell_apk/MainActivity.java

Index: chrome/android/webapk/shell_apk/src/org/chromium/webapk/shell_apk/MainActivity.java
diff --git a/chrome/android/webapk/shell_apk/src/org/chromium/webapk/shell_apk/MainActivity.java b/chrome/android/webapk/shell_apk/src/org/chromium/webapk/shell_apk/MainActivity.java
index e30875d3a331c1bbdfff0a3290f591ff735ed751..1f37399a6b5895d6592382070029a0be23d04333 100644
--- a/chrome/android/webapk/shell_apk/src/org/chromium/webapk/shell_apk/MainActivity.java
+++ b/chrome/android/webapk/shell_apk/src/org/chromium/webapk/shell_apk/MainActivity.java
@@ -17,8 +17,6 @@ import android.util.Log;
 import org.chromium.webapk.lib.common.WebApkConstants;
 import org.chromium.webapk.lib.common.WebApkMetaDataKeys;
 
-import java.net.URISyntaxException;
-
 /**
  * WebAPK's main Activity.
  */
@@ -76,9 +74,7 @@ public class MainActivity extends Activity {
         if (launchHostBrowserInWebApkMode(startUrl, overrideUrl)) {
             return;
         }
-        if (launchBrowser(startUrl)) {
-            return;
-        }
+
         installBrowser();
     }
 
@@ -92,6 +88,8 @@ public class MainActivity extends Activity {
         Log.v(TAG, "Package name of the WebAPK:" + packageName);
 
         String runtimeHost = WebApkUtils.getHostBrowserPackageName(this);
+        if (runtimeHost == null) return false;
+
         boolean isFromExternalIntent = (overrideUrl != null);
         int source = getIntent().getIntExtra(WebApkConstants.EXTRA_SOURCE, 0);
         if (isFromExternalIntent && source == WebApkConstants.SHORTCUT_SOURCE_UNKNOWN) {
@@ -118,46 +116,11 @@ public class MainActivity extends Activity {
         }
     }
 
-    /**
-     * Launches browser (not necessarily the host browser).
-     * @param startUrl URL to navigate browser to.
-     * @return True if successful.
-     */
-    private boolean launchBrowser(String startUrl) {
-        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(startUrl));
-        intent.addCategory(Intent.CATEGORY_BROWSABLE);
-
-        // The WebAPK can handle {@link startUrl}. Set a selector to prevent the WebAPK from
-        // launching itself.
-        try {
-            Intent selectorIntent = Intent.parseUri("https://", Intent.URI_INTENT_SCHEME);
-            intent.setSelector(selectorIntent);
-        } catch (URISyntaxException e) {
-            return false;
-        }
-
-        // Add extras in case that the URL is launched in Chrome.
-        int source =
-                getIntent().getIntExtra(WebApkConstants.EXTRA_SOURCE, Intent.URI_INTENT_SCHEME);
-        intent.putExtra(REUSE_URL_MATCHING_TAB_ELSE_NEW_TAB, true)
-              .putExtra(WebApkConstants.EXTRA_SOURCE, source);
-
-        try {
-            startActivity(intent);
-        } catch (ActivityNotFoundException e) {
-            return false;
-        }
-        return true;
-    }
-
     /**
      * Launches the Play Store with the host browser's page.
      */
     private void installBrowser() {
-        String hostBrowserPackageName = WebApkUtils.getHostBrowserPackageName(this);
-        if (hostBrowserPackageName == null) {
-            return;
-        }
+        String hostBrowserPackageName = WebApkConstants.DEFAULT_HOST_BROWSER;
 
         try {
             startActivity(createInstallIntent(hostBrowserPackageName));