Add UMA metric to track the time elapsed since a WebAPK was last launched

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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
index 9c85fda3d5e709d921f9b00197216815577ed8d2..650fcb7dae17c9d1552bc9e133e6c5678f3ca1d8 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDataStorage.java
@@ -33,6 +33,7 @@ public class WebappDataStorage {
     static final String SHARED_PREFS_FILE_PREFIX = "webapp_";
     static final String KEY_SPLASH_ICON = "splash_icon";
     static final String KEY_LAST_USED = "last_used";
+    static final String KEY_HAS_BEEN_LAUNCHED = "has_been_launched";
     static final String KEY_URL = "url";
     static final String KEY_SCOPE = "scope";
     static final String KEY_ICON = "icon";
@@ -291,10 +292,12 @@ public class WebappDataStorage {
     }
 
     /**
-     * Returns true if this web app has been launched from home screen recently (within
-     * WEBAPP_LAST_OPEN_MAX_TIME milliseconds).
+     * Returns true if this web app recently (within WEBAPP_LAST_OPEN_MAX_TIME milliseconds) was
+     * either:
+     * - registered with WebappRegistry
+     * - launched from the homescreen
      */
-    public boolean wasLaunchedRecently() {
+    public boolean wasUsedRecently() {
         // WebappRegistry.register sets the last used time, so that counts as a 'launch'.
         return (sClock.currentTimeMillis() - getLastUsedTime() < WEBAPP_LAST_OPEN_MAX_TIME);
     }
@@ -315,6 +318,7 @@ public class WebappDataStorage {
         SharedPreferences.Editor editor = mPreferences.edit();
 
         editor.remove(KEY_LAST_USED);
+        editor.remove(KEY_HAS_BEEN_LAUNCHED);
         editor.remove(KEY_URL);
         editor.remove(KEY_SCOPE);
         editor.remove(KEY_LAST_CHECK_WEB_MANIFEST_UPDATE_TIME);
@@ -374,6 +378,16 @@ public class WebappDataStorage {
         mPreferences.edit().putLong(KEY_LAST_USED, sClock.currentTimeMillis()).apply();
     }
 
+    /** Returns true if the web app has been launched at least once from the home screen. */
+    boolean hasBeenLaunched() {
+        return mPreferences.getBoolean(KEY_HAS_BEEN_LAUNCHED, false);
+    }
+
+    /** Sets whether the web app was launched at least once from the home screen. */
+    void setHasBeenLaunched() {
+        mPreferences.edit().putBoolean(KEY_HAS_BEEN_LAUNCHED, true).apply();
+    }
+
     /**
      * Returns the package name if the data is for a WebAPK, null otherwise.
      */