Upstream oodles of Chrome for Android code into Chromium.

chrome/android/java_staging/src/org/chromium/chrome/browser/omaha/VersionNumberGetter.java

Index: chrome/android/java_staging/src/org/chromium/chrome/browser/omaha/VersionNumberGetter.java
diff --git a/chrome/android/java_staging/src/org/chromium/chrome/browser/omaha/VersionNumberGetter.java b/chrome/android/java_staging/src/org/chromium/chrome/browser/omaha/VersionNumberGetter.java
new file mode 100644
index 0000000000000000000000000000000000000000..071d74e3fce68748147c064f6b642cfbd89ebb99
--- /dev/null
+++ b/chrome/android/java_staging/src/org/chromium/chrome/browser/omaha/VersionNumberGetter.java
@@ -0,0 +1,38 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.omaha;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.os.Looper;
+
+import org.chromium.base.BuildInfo;
+
+/**
+ * Stubbed class for getting version numbers from the rest of Chrome.  Override the functions for
+ * unit tests.
+ */
+public class VersionNumberGetter {
+    /**
+     * Retrieve the latest version we know about from disk.
+     * This function incurs I/O, so make sure you don't use it from the main thread.
+     * @return The latest version if we retrieved one from the Omaha server, or "" if we haven't.
+     */
+    public String getLatestKnownVersion(
+            Context applicationContext, String prefPackage, String prefLatestVersion) {
+        assert Looper.myLooper() != Looper.getMainLooper();
+        SharedPreferences prefs = applicationContext.getSharedPreferences(
+                prefPackage, Context.MODE_PRIVATE);
+        return prefs.getString(prefLatestVersion, "");
+    }
+
+    /**
+     * Retrieve the version of Chrome we're using.
+     * @return The latest version if we retrieved one from the Omaha server, or "" if we haven't.
+     */
+    public String getCurrentlyUsedVersion(Context applicationContext) {
+        return BuildInfo.getPackageVersionName(applicationContext);
+    }
+}