Reland of Add integration tests for WebAPKs

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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkUpdateManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkUpdateManager.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkUpdateManager.java
index 3c4bd649acc5159c4475ebd082fb6d99abd44b54..68943599223d5846481232b1b6c1e9e9712ad2d2 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkUpdateManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkUpdateManager.java
@@ -46,6 +46,9 @@
      */
     private static final int MAX_UPDATE_ATTEMPTS = 3;
 
+    /** Whether updates are enabled. Some tests disable updates. */
+    private static boolean sUpdatesEnabled = true;
+
     /** Data extracted from the WebAPK's launch intent and from the WebAPK's Android Manifest. */
     private WebApkInfo mInfo;
 
@@ -122,6 +125,10 @@
 
     public boolean getHasPendingUpdateForTesting() {
         return mPendingUpdate != null;
+    }
+
+    public static void setUpdatesEnabledForTesting(boolean enabled) {
+        sUpdatesEnabled = enabled;
     }
 
     @Override
@@ -308,6 +315,10 @@
      */
     private boolean shouldCheckIfWebManifestUpdated(
             WebappDataStorage storage, WebApkInfo info, boolean previousUpdateSucceeded) {
+        if (!sUpdatesEnabled) {
+            return false;
+        }
+
         if (CommandLine.getInstance().hasSwitch(
                     ChromeSwitches.CHECK_FOR_WEB_MANIFEST_UPDATE_ON_STARTUP)) {
             return true;