Added basic browser test for window.print() from Chrome apps.

chrome/test/data/extensions/platform_apps/print_api/test.js

Index: chrome/test/data/extensions/platform_apps/print_api/test.js
diff --git a/chrome/test/data/extensions/platform_apps/print_api/test.js b/chrome/test/data/extensions/platform_apps/print_api/test.js
new file mode 100644
index 0000000000000000000000000000000000000000..eb132cbf67a69fa7c0e72aa9ecf4b090cf22fcde
--- /dev/null
+++ b/chrome/test/data/extensions/platform_apps/print_api/test.js
@@ -0,0 +1,14 @@
+chrome.app.runtime.onLaunched.addListener(function() {
+  chrome.test.runTests([
+    function testWindowDotPrintCallWorks() {
+      chrome.app.window.create('test.html', {}, chrome.test.callbackPass(
+          function(appWindow) {
+            appWindow.contentWindow.onload = chrome.test.callbackPass(
+                function() {
+                  appWindow.contentWindow.print();
+                  chrome.test.notifyPass();

[asargent_no_longer_on_chrome, 2013/08/13 22:38:54]

nit: I don't think you need this final call here - each invocation of
callbackPass should increment the counter of "pending callbacks that need to not
fail for the overall test to succeed", so just exiting out of this scope without
failing should be sufficient (I think). 

[dharcourt, 2013/08/13 23:06:31]

Fixed, thanks! I thought I had tried that earlier but it must have been before I
was using callbackPass() correctly because it wasn't working then. Now it is
:-).

On 2013/08/13 22:38:54, Antony Sargent wrote:

+                });
+          }));
+    }
+  ]);
+});