Revert of Enable all ESC-Fullscreen tests (Chrome Apps) for all platforms.

chrome/test/data/extensions/platform_apps/leave_fullscreen/main.js

Index: chrome/test/data/extensions/platform_apps/leave_fullscreen/main.js
diff --git a/chrome/test/data/extensions/platform_apps/leave_fullscreen/main.js b/chrome/test/data/extensions/platform_apps/leave_fullscreen/main.js
index 95940b1c3f67c163a0088d040af1dc6863aaaf7d..109bccf88f97724024efc2dab190a1b785632da4 100644
--- a/chrome/test/data/extensions/platform_apps/leave_fullscreen/main.js
+++ b/chrome/test/data/extensions/platform_apps/leave_fullscreen/main.js
@@ -14,13 +14,6 @@
     });
 
     chrome.test.sendMessage('Launched', function(reply) {
-      win.contentWindow.document.addEventListener('keydown', function(e) {
-        if (e.keyCode != 90) // 'z'
-          return;
-
-        chrome.test.sendMessage('KeyReceived');
-      });
-
       switch (reply) {
         case 'window':
           win.fullscreen();