[Android Webapps] Remove context function parameters from WebappLauncherActivity

This CL removes the application context parameter from several functions in
WebappLauncherActivity and WebappAuthenticator.

BUG=None

Change-Id: Ie4486cb4f9950a34e6b8349806cab35ebbb8f5a0
Reviewed-on: https://chromium-review.googlesource.com/c/1354128
Commit-Queue: Peter Kotwicz <pkotwicz@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612742}

chrome/android/java/src/org/chromium/chrome/browser/ShortcutHelper.java

@@ -168,8 +168,6 @@ public class ShortcutHelper {
             protected Intent doInBackground() {
                 // Encoding {@link icon} as a string and computing the mac are expensive.
 
-                Context context = ContextUtils.getApplicationContext();
-
                 // Encode the icon as a base64 string (Launcher drops Bitmaps in the Intent).
                 String encodedIcon = encodeBitmapAsString(icon);
 
@@ -179,7 +177,7 @@ public class ShortcutHelper {
                         sDelegate.getFullscreenAction(), url, nonEmptyScopeUrl, name, shortName,
                         encodedIcon, WEBAPP_SHORTCUT_VERSION, displayMode, orientation, themeColor,
                         backgroundColor, splashScreenUrl, iconUrl.isEmpty());
-                shortcutIntent.putExtra(EXTRA_MAC, getEncodedMac(context, url));
+                shortcutIntent.putExtra(EXTRA_MAC, getEncodedMac(url));
                 shortcutIntent.putExtra(EXTRA_SOURCE, source);
                 return shortcutIntent;
             }
@@ -590,11 +588,11 @@ public class ShortcutHelper {
     /**
      * @return String that can be used to verify that a WebappActivity is being started by Chrome.
      */
-    public static String getEncodedMac(Context context, String url) {
+    public static String getEncodedMac(String url) {
         // The only reason we convert to a String here is because Android inexplicably eats a
         // byte[] when adding the shortcut -- the Bundle received by the launched Activity even
         // lacks the key for the extra.
-        byte[] mac = WebappAuthenticator.getMacForUrl(context, url);
+        byte[] mac = WebappAuthenticator.getMacForUrl(url);
         return Base64.encodeToString(mac, Base64.DEFAULT);
     }
 

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappAuthenticator.java

@@ -11,6 +11,7 @@ import android.os.SystemClock;
 import android.util.Log;
 
 import org.chromium.base.ApiCompatibilityUtils;
+import org.chromium.base.ContextUtils;
 import org.chromium.base.SecureRandomInitializer;
 import org.chromium.base.metrics.CachedMetrics.TimesHistogramSample;
 import org.chromium.base.task.AsyncTask;
@@ -61,13 +62,13 @@ public class WebappAuthenticator {
      *
      * @return true if the MAC is a valid MAC for the URL, false otherwise.
      */
-    public static boolean isUrlValid(Context context, String url, byte[] mac) {
+    public static boolean isUrlValid(String url, byte[] mac) {
         byte[] goodMac = null;
         // Temporarily allowing disk access while fixing. TODO: http://crbug.com/525785
         StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
         try {
             long time = SystemClock.elapsedRealtime();
-            goodMac = getMacForUrl(context, url);
+            goodMac = getMacForUrl(url);
             sWebappValidationTimes.record(SystemClock.elapsedRealtime() - time);
         } finally {
             StrictMode.setThreadPolicy(oldPolicy);
@@ -85,8 +86,8 @@ public class WebappAuthenticator {
      *
      * @return The bytes of a MAC for the URL, or null if a secure MAC was not available.
      */
-    public static byte[] getMacForUrl(Context context, String url) {
-        Mac mac = getMac(context);
+    public static byte[] getMacForUrl(String url) {
+        Mac mac = getMac();
         if (mac == null) {
             return null;
         }
@@ -169,9 +170,10 @@ public class WebappAuthenticator {
         }
     }
 
-    private static SecretKey getKey(Context context) {
+    private static SecretKey getKey() {
         synchronized (sLock) {
             if (sKey == null) {
+                Context context = ContextUtils.getApplicationContext();
                 SecretKey key = readKeyFromFile(context, MAC_KEY_BASENAME, MAC_ALGORITHM_NAME);
                 if (key != null) {
                     sKey = key;
@@ -226,9 +228,9 @@ public class WebappAuthenticator {
     /**
      * @return A Mac, or null if it is not possible to instantiate one.
      */
-    private static Mac getMac(Context context) {
+    private static Mac getMac() {
         try {
-            SecretKey key = getKey(context);
+            SecretKey key = getKey();
             if (key == null) {
                 // getKey should have invoked triggerMacKeyGeneration, which should have set the
                 // random seed and generated a key from it. If not, there is a problem with the

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDelegateFactory.java

@@ -54,8 +54,7 @@ public class WebappDelegateFactory extends TabDelegateFactory {
             intent.setPackage(mActivity.getPackageName());
             mActivity.getWebappInfo().setWebappIntentExtras(intent);
 
-            intent.putExtra(
-                    ShortcutHelper.EXTRA_MAC, ShortcutHelper.getEncodedMac(mActivity, startUrl));
+            intent.putExtra(ShortcutHelper.EXTRA_MAC, ShortcutHelper.getEncodedMac(startUrl));
             intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
             IntentUtils.safeStartActivity(ContextUtils.getApplicationContext(), intent);
         }

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappLauncherActivity.java

@@ -59,17 +59,16 @@ public class WebappLauncherActivity extends Activity {
         super.onCreate(savedInstanceState);
         long createTimestamp = SystemClock.elapsedRealtime();
 
-        Context appContext = getApplicationContext();
         ChromeWebApkHost.init();
         Intent intent = getIntent();
-        WebappInfo webappInfo = tryCreateWebappInfo(appContext, intent);
+        WebappInfo webappInfo = tryCreateWebappInfo(intent);
 
         if (shouldRelaunchWebApk(intent, webappInfo)) {
             relaunchWebApk(this, intent, webappInfo);
             return;
         }
 
-        if (shouldLaunchWebapp(appContext, intent, webappInfo)) {
+        if (shouldLaunchWebapp(intent, webappInfo)) {
             launchWebapp(this, intent, webappInfo, createTimestamp);
             return;
         }
@@ -77,8 +76,7 @@ public class WebappLauncherActivity extends Activity {
         launchInTab(this, intent, webappInfo);
     }
 
-    private static boolean shouldLaunchWebapp(
-            Context appContext, Intent intent, WebappInfo webappInfo) {
+    private static boolean shouldLaunchWebapp(Intent intent, WebappInfo webappInfo) {
         // {@link WebApkInfo#create()} and {@link WebappInfo#create()} return null if the intent
         // does not specify required values such as the uri.
         if (webappInfo == null) return false;
@@ -86,7 +84,7 @@ public class WebappLauncherActivity extends Activity {
         String webappUrl = webappInfo.uri().toString();
         String webappMac = IntentUtils.safeGetStringExtra(intent, ShortcutHelper.EXTRA_MAC);
 
-        return (webappInfo.isForWebApk() || isValidMacForUrl(appContext, webappUrl, webappMac)
+        return (webappInfo.isForWebApk() || isValidMacForUrl(webappUrl, webappMac)
                 || wasIntentFromChrome(intent));
     }
 
@@ -176,7 +174,7 @@ public class WebappLauncherActivity extends Activity {
     /** Extracts start URL from source intent and launches URL in Chrome tab. */
     private static void launchInTab(
             Activity launchingActivity, Intent sourceIntent, WebappInfo webappInfo) {
-        Context appContext = launchingActivity.getApplicationContext();
+        Context appContext = ContextUtils.getApplicationContext();
         String webappUrl = IntentUtils.safeGetStringExtra(sourceIntent, ShortcutHelper.EXTRA_URL);
         int webappSource = (webappInfo == null) ? ShortcutSource.UNKNOWN : webappInfo.source();
 
@@ -202,14 +200,13 @@ public class WebappLauncherActivity extends Activity {
      * The MAC is used to prevent malicious apps from launching Chrome into a full screen
      * Activity for phishing attacks (among other reasons).
      *
-     * @param context
      * @param url The URL for the web app.
      * @param mac MAC to compare the URL against.  See {@link WebappAuthenticator}.
      * @return Whether the MAC is valid for the URL.
      */
-    private static boolean isValidMacForUrl(Context context, String url, String mac) {
+    private static boolean isValidMacForUrl(String url, String mac) {
         return mac != null
-                && WebappAuthenticator.isUrlValid(context, url, Base64.decode(mac, Base64.DEFAULT));
+                && WebappAuthenticator.isUrlValid(url, Base64.decode(mac, Base64.DEFAULT));
     }
 
     private static boolean wasIntentFromChrome(Intent intent) {
@@ -315,14 +312,15 @@ public class WebappLauncherActivity extends Activity {
     }
 
     /** Tries to create WebappInfo/WebApkInfo for the intent. */
-    private static WebappInfo tryCreateWebappInfo(Context appContext, Intent intent) {
+    private static WebappInfo tryCreateWebappInfo(Intent intent) {
         // Builds WebApkInfo for the intent if the WebAPK package specified in the intent is a valid
         // WebAPK and the URL specified in the intent can be fulfilled by the WebAPK.
         String webApkPackage =
                 IntentUtils.safeGetStringExtra(intent, WebApkConstants.EXTRA_WEBAPK_PACKAGE_NAME);
         String url = IntentUtils.safeGetStringExtra(intent, ShortcutHelper.EXTRA_URL);
         if (!TextUtils.isEmpty(webApkPackage) && !TextUtils.isEmpty(url)
-                && WebApkValidator.canWebApkHandleUrl(appContext, webApkPackage, url)) {
+                && WebApkValidator.canWebApkHandleUrl(
+                        ContextUtils.getApplicationContext(), webApkPackage, url)) {
             return WebApkInfo.create(intent);
         }
 

chrome/android/javatests/src/org/chromium/chrome/browser/webapps/WebappAuthenticatorTest.java

@@ -4,7 +4,6 @@
 
 package org.chromium.chrome.browser.webapps;
 
-import android.content.Context;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.filters.SmallTest;
 
@@ -14,6 +13,7 @@ import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
+import org.chromium.base.ContextUtils;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.test.util.Feature;
 import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
@@ -37,13 +37,13 @@ public class WebappAuthenticatorTest {
     @SmallTest
     @Feature({"Webapps"})
     public void testAuthentication() {
-        Context context = InstrumentationRegistry.getTargetContext();
+        ContextUtils.initApplicationContextForTests(InstrumentationRegistry.getTargetContext());
         String url = "http://www.example.org/hello.html";
-        byte[] mac = WebappAuthenticator.getMacForUrl(context, url);
+        byte[] mac = WebappAuthenticator.getMacForUrl(url);
         Assert.assertNotNull(mac);
-        Assert.assertTrue(WebappAuthenticator.isUrlValid(context, url, mac));
-        Assert.assertFalse(WebappAuthenticator.isUrlValid(context, url + "?goats=true", mac));
+        Assert.assertTrue(WebappAuthenticator.isUrlValid(url, mac));
+        Assert.assertFalse(WebappAuthenticator.isUrlValid(url + "?goats=true", mac));
         mac[4] += (byte) 1;
-        Assert.assertFalse(WebappAuthenticator.isUrlValid(context, url, mac));
+        Assert.assertFalse(WebappAuthenticator.isUrlValid(url, mac));
     }
 }

chrome/android/javatests/src/org/chromium/chrome/browser/webapps/WebappModeTest.java

@@ -83,8 +83,7 @@ public class WebappModeTest {
         if (addMac) {
             // Needed for security reasons.  If the MAC is excluded, the URL of the webapp is opened
             // in a browser window, instead.
-            String mac =
-                    ShortcutHelper.getEncodedMac(InstrumentationRegistry.getTargetContext(), url);
+            String mac = ShortcutHelper.getEncodedMac(url);
             intent.putExtra(ShortcutHelper.EXTRA_MAC, mac);
         }