Make Clipboard.java a singleton pattern.

chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManager.java b/chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManager.java
index 61bf103fa4306957174c29a087f5c4142095c6f5..ff156126c6f53e34afd624a8fa44b992d2735bf9 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/history/HistoryManager.java
@@ -182,8 +182,7 @@ public class HistoryManager implements OnMenuItemClickListener, SignInStateObser
             return true;
         } else if (item.getItemId() == R.id.selection_mode_copy_link) {
             recordUserActionWithOptionalSearch("CopyLink");
-            Clipboard clipboard = new Clipboard(mActivity);
-            clipboard.setText(mSelectionDelegate.getSelectedItems().get(0).getUrl());
+            Clipboard.getInstance().setText(mSelectionDelegate.getSelectedItems().get(0).getUrl());
             mSelectionDelegate.clearSelection();
             Snackbar snackbar = Snackbar.make(mActivity.getString(R.string.copied), this,
                     Snackbar.TYPE_NOTIFICATION, Snackbar.UMA_HISTORY_LINK_COPIED);