Add an about:flag to control WebApk enablement.

chrome/android/javatests/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandlerTest.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandlerTest.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandlerTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandlerTest.java
index 69394748bbf43d514f80a325db90c02126782e6b..320f3d7486896a85a898357623799e0f02e701de 100644
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandlerTest.java
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/externalnav/ExternalNavigationHandlerTest.java
@@ -19,14 +19,13 @@ import android.test.mock.MockContext;
 import android.test.mock.MockPackageManager;
 import android.test.suitebuilder.annotation.SmallTest;
 
-import org.chromium.base.CommandLine;
 import org.chromium.base.metrics.RecordHistogram;
-import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.chrome.browser.externalnav.ExternalNavigationHandler.OverrideUrlLoadingResult;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tab.TabRedirectHandler;
 import org.chromium.chrome.browser.util.FeatureUtilities;
+import org.chromium.chrome.browser.webapps.ChromeWebApkHost;
 import org.chromium.ui.base.PageTransition;
 import org.chromium.webapk.lib.common.WebApkConstants;
 
@@ -110,9 +109,9 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
     protected void setUp() throws Exception {
         super.setUp();
         mDelegate.setContext(getInstrumentation().getTargetContext());
-        CommandLine.init(new String[0]);
         RecordHistogram.disableForTests();
         mDelegate.mQueryIntentOverride = null;
+        ChromeWebApkHost.initForTesting(false);  // disabled by default
     }
 
     @SmallTest
@@ -864,10 +863,10 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
 
     /**
      * Test that tapping a link which falls solely into the scope of a WebAPK does not bypass the
-     * intent picker if WebAPKs are disabled in the command line.
+     * intent picker if WebAPKs are not enabled.
      */
     @SmallTest
-    public void testLaunchWebApk_WebApkDisabledCommandLine() {
+    public void testLaunchWebApk_WebApkNotEnabled() {
         checkUrl(WEBAPK_SCOPE)
                 .expecting(OverrideUrlLoadingResult.OVERRIDE_WITH_EXTERNAL_INTENT,
                         START_OTHER_ACTIVITY);
@@ -875,11 +874,11 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
 
     /**
      * Test that tapping a link which falls solely in the scope of a WebAPK launches a WebAPK
-     * without showing the intent picker if WebAPKs are enabled in the command line.
+     * without showing the intent picker if WebAPKs are enabled.
      */
     @SmallTest
     public void testLaunchWebApk_BypassIntentPicker() {
-        CommandLine.getInstance().appendSwitch(ChromeSwitches.ENABLE_WEBAPK);
+        ChromeWebApkHost.initForTesting(true);
         checkUrl(WEBAPK_SCOPE)
                 .expecting(OverrideUrlLoadingResult.OVERRIDE_WITH_EXTERNAL_INTENT, START_WEBAPK);
     }
@@ -890,7 +889,7 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
      */
     @SmallTest
     public void testLaunchWebApk_ShowIntentPickerMultipleIntentHandlers() {
-        CommandLine.getInstance().appendSwitch(ChromeSwitches.ENABLE_WEBAPK);
+        ChromeWebApkHost.initForTesting(true);
         checkUrl(WEBAPK_WITH_NATIVE_APP_SCOPE)
                 .expecting(OverrideUrlLoadingResult.OVERRIDE_WITH_EXTERNAL_INTENT,
                         START_OTHER_ACTIVITY);
@@ -902,7 +901,7 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
      */
     @SmallTest
     public void testLaunchWebApk_BypassIntentPickerFromAnotherWebApk() {
-        CommandLine.getInstance().appendSwitch(ChromeSwitches.ENABLE_WEBAPK);
+        ChromeWebApkHost.initForTesting(true);
         checkUrl(WEBAPK_SCOPE)
                 .withReferrer(WEBAPK_WITH_NATIVE_APP_SCOPE)
                 .withWebApkPackageName(WEBAPK_WITH_NATIVE_APP_PACKAGE_NAME)
@@ -916,7 +915,7 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
      */
     @SmallTest
     public void testLaunchWebApk_ShowIntentPickerInvalidWebApk() {
-        CommandLine.getInstance().appendSwitch(ChromeSwitches.ENABLE_WEBAPK);
+        ChromeWebApkHost.initForTesting(true);
         checkUrl(COUNTERFEIT_WEBAPK_SCOPE)
                 .expecting(OverrideUrlLoadingResult.OVERRIDE_WITH_EXTERNAL_INTENT,
                         START_OTHER_ACTIVITY);
@@ -928,7 +927,7 @@ public class ExternalNavigationHandlerTest extends InstrumentationTestCase {
      */
     @SmallTest
     public void testLaunchWebApk_StayInSameWebApk() {
-        CommandLine.getInstance().appendSwitch(ChromeSwitches.ENABLE_WEBAPK);
+        ChromeWebApkHost.initForTesting(true);
         checkUrl(WEBAPK_SCOPE + "/new.html")
                 .withWebApkPackageName(WEBAPK_PACKAGE_NAME)
                 .expecting(OverrideUrlLoadingResult.NO_OVERRIDE, IGNORE);