Refactor Clipboard Last Modified Time Storage

ui/base/clipboard/clipboard_android.h

Index: ui/base/clipboard/clipboard_android.h
diff --git a/ui/base/clipboard/clipboard_android.h b/ui/base/clipboard/clipboard_android.h
index a41550a24819d234ab4aa5b38eab136ccd0fc401..c194997439a5f7e717dce783115392f55d6ef2f2 100644
--- a/ui/base/clipboard/clipboard_android.h
+++ b/ui/base/clipboard/clipboard_android.h
@@ -11,11 +11,25 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
+#include "base/time/time.h"
+
+class PrefRegistrySimple;
 
 namespace ui {
 
-class ClipboardAndroid : public Clipboard {
+// Exported only so chrome/browser/android/preferences/browser_prefs_android.cc
+// can call RegisterPrefs().
+class UI_BASE_EXPORT ClipboardAndroid : public Clipboard {
+ public:
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+
+  // Called by Java when the Java Clipboard is notified that the clipboard has
+  // changed.
+  void OnPrimaryClipChanged(JNIEnv* env,
+                            const base::android::JavaParamRef<jobject>& obj);
+
  private:
   friend class Clipboard;
 
@@ -46,6 +60,7 @@ class ClipboardAndroid : public Clipboard {
   void ReadBookmark(base::string16* title, std::string* url) const override;
   void ReadData(const FormatType& format, std::string* result) const override;
   base::Time GetClipboardLastModifiedTime() const override;
+  void ClearClipboardLastModifiedTime() override;
   void WriteObjects(ClipboardType type, const ObjectMap& objects) override;
   void WriteText(const char* text_data, size_t text_len) override;
   void WriteHTML(const char* markup_data,
@@ -66,6 +81,9 @@ class ClipboardAndroid : public Clipboard {
   DISALLOW_COPY_AND_ASSIGN(ClipboardAndroid);
 };
 
+// Registers the ClipboardAndroid native method.
+bool RegisterClipboardAndroid(JNIEnv* env);
+
 }  // namespace ui
 
 #endif  // UI_BASE_CLIPBOARD_CLIPBOARD_ANDROID_H_