Refactor Android printing code to make it more testable.

chrome/android/java/src/org/chromium/chrome/browser/printing/TabPrinter.java

Index: chrome/android/java/src/org/chromium/chrome/browser/printing/TabPrinter.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/printing/TabPrinter.java b/chrome/android/java/src/org/chromium/chrome/browser/printing/TabPrinter.java
new file mode 100644
index 0000000000000000000000000000000000000000..a5223085261bb18448887a753216cd539047fcf8
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/printing/TabPrinter.java
@@ -0,0 +1,52 @@
+// Copyright 2013 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.printing;
+
+import android.text.TextUtils;
+
+import org.chromium.chrome.browser.TabBase;
+import org.chromium.printing.Printable;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * Wraps printing related functionality of a {@link TabBase} object.
+ *
+ * This class doesn't have any lifetime expectations with regards to Tab, since we keep a weak
+ * reference.
+ */
+public class TabPrinter implements Printable {
+    private static String sDefaultTitle;
+
+    private final WeakReference<TabBase> mTab;
+
+    public TabPrinter(TabBase tab) {
+        mTab = new WeakReference<TabBase>(tab);
+    }
+
+    public static void setDefaultTitle(String defaultTitle) {
+        sDefaultTitle = defaultTitle;
+    }
+
+    @Override
+    public boolean print() {
+        TabBase tab = mTab.get();
+        return tab != null && tab.print();
+    }
+
+    @Override
+    public String getTitle() {
+        TabBase tab = mTab.get();
+        if (tab == null) return sDefaultTitle;
+
+        String title = tab.getTitle();
+        if (!TextUtils.isEmpty(title)) return title;
+
+        String url = tab.getUrl();
+        if (!TextUtils.isEmpty(url)) return url;
+
+        return sDefaultTitle;
+    }
+}