Added a browser test of the print preview dialog size for 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
index b041f16e9edf61bc20236abe2f6d7f3eee79b52b..8e9966ee84d6ad24fd5b41c16a2989ea91374ab9 100644
--- a/chrome/test/data/extensions/platform_apps/print_api/test.js
+++ b/chrome/test/data/extensions/platform_apps/print_api/test.js
@@ -4,7 +4,8 @@
 
 chrome.app.runtime.onLaunched.addListener(function() {
   chrome.test.getConfig(function(config) {
-    chrome.app.window.create('test.html', {}, function(appWindow) {
+    var options = {bounds: {width: 200, height: 100}};
+    chrome.app.window.create('test.html', options, function(appWindow) {
       appWindow.contentWindow.onload = function() {
         appWindow.contentWindow.print();
         chrome.test.notifyPass();