Remove left-over PageCache stuff

LayoutTests/fast/dom/DeviceMotion/script-tests/no-page-cache.js

-description('Tests that pages that use DeviceMotion are not put in the page cache.');
-
-if (window.testRunner) {
-    testRunner.waitUntilDone();
-    testRunner.setCanOpenWindows();
-    testRunner.overridePreference('WebKitUsesPageCachePreferenceKey', 1);
-} else
-    debug('This test can not be run without the TestRunner');
-
-var pageOneOnloadCount = 0;
-function reportPageOneOnload() {
-    ++pageOneOnloadCount;
-    debug('resources/cached-page-1.html onload fired, count = ' + pageOneOnloadCount);
-    if (pageOneOnloadCount == 2) {
-        finishJSTest();
-    }
-    return pageOneOnloadCount;
-}
-
-debug("Main page opening resources/cached-page-1.html");
-window.open("resources/cached-page-1.html");
-
-window.jsTestIsAsync = true;