Improve <webview> autosize:

chrome/test/data/extensions/platform_apps/web_view/shim/main.js

 // Copyright (c) 2012 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.
 
 var util = {};
 var embedder = {};
 embedder.baseGuestURL = '';
 embedder.emptyGuestURL = '';
 embedder.windowOpenGuestURL = '';
 embedder.noReferrerGuestURL = '';
@@ skipping 166 matching lines @@
         embedder.test.assertEq(200, e.newHeight);
 
         // Remove an autosize attribute and verify that it causes relayout.
         webview.minwidth = null;
         break;
       case 2:
         // Expect 640x?
         embedder.test.assertEq(640, e.newWidth);
 
         // Tests when minwidth > maxwidth, minwidth = maxwidth.
-        webview.maxheight = null;
         webview.minwidth = 800;
-        webview.minheight = 800;
         break;
       case 3:
-        // Expect 700X480
+        // Expect 700X?
         embedder.test.assertEq(700, e.newWidth);
-        embedder.test.assertEq(480, e.newHeight);
+        embedder.test.assertTrue(e.newHeight >= 200);
+        embedder.test.assertTrue(e.newHeight <= 600);
 
         // Remove maxwidth and make sure the size returns to plugin size.
         webview.removeAttribute('maxwidth');
         break;
       case 4:
         // Expect original size, 640x480.
         embedder.test.assertEq(640, e.newWidth);
-        embedder.test.assertEq(480, e.newHeight);
+        embedder.test.assertTrue(e.newHeight >= 200);
+        embedder.test.assertTrue(e.newHeight <= 600);
 
         embedder.test.succeed();
         break;
       default:
         window.console.log('Unexpected sizechanged event, step = ' + step);
         embedder.test.fail();
         break;
     }
 
     ++step;
@@ skipping 715 matching lines @@
   'testRemoveWebviewAfterNavigation': testRemoveWebviewAfterNavigation,
   'testResizeWebviewResizesContent': testResizeWebviewResizesContent
 };
 
 onload = function() {
   chrome.test.getConfig(function(config) {
     embedder.setUp_(config);
     chrome.test.sendMessage("Launched");
   });
 };