Bug 966612 part.2 Add tests on printpreview UI r=enndeakin

browser/base/content/test/general/browser.ini

@@ -288,6 +288,7 @@ run-if = crashreporter
 [browser_popupNotification.js]
 skip-if = toolkit == "windows" # Disabled on Windows due to frequent failures (bugs 825739, 841341)
 [browser_popupUI.js]
+[browser_printpreview.js]
 [browser_private_browsing_window.js]
 [browser_private_no_prompt.js]
 [browser_relatedTabs.js]

browser/base/content/test/general/browser_printpreview.js

@@ -0,0 +1,65 @@
+function test() {
+  waitForExplicitFinish();
+
+  ok(!gInPrintPreviewMode,
+     "Should NOT be in print preview mode at starting this tests");
+  // Skip access key test on platforms which don't support access key.
+  if (!/Win|Linux/.test(navigator.platform)) {
+    openPrintPreview(testClosePrintPreviewWithEscKey);
+  } else {
+    openPrintPreview(testClosePrintPreviewWithAccessKey);
+  }
+}
+
+function testClosePrintPreviewWithAccessKey() {
+  EventUtils.synthesizeKey("c", { altKey: true });
+  checkPrintPreviewClosed(function (aSucceeded) {
+    ok(aSucceeded,
+       "print preview mode should be finished by access key");
+    openPrintPreview(testClosePrintPreviewWithEscKey);
+  });
+}
+
+function testClosePrintPreviewWithEscKey() {
+  EventUtils.synthesizeKey("VK_ESCAPE", {});
+  checkPrintPreviewClosed(function (aSucceeded) {
+    ok(aSucceeded,
+       "print preview mode should be finished by Esc key press");
+    openPrintPreview(testClosePrintPreviewWithClosingWindowShortcutKey);
+  });
+}
+
+function testClosePrintPreviewWithClosingWindowShortcutKey() {
+  EventUtils.synthesizeKey("w", { accelKey: true });
+  checkPrintPreviewClosed(function (aSucceeded) {
+    ok(aSucceeded,
+       "print preview mode should be finished by closing window shortcut key");
+    finish();
+  });
+}
+
+function openPrintPreview(aCallback) {
+  document.getElementById("cmd_printPreview").doCommand();
+  executeSoon(function () {
+    if (gInPrintPreviewMode) {
+      executeSoon(aCallback);
+      return;
+    }
+    executeSoon(arguments.callee);
+  });
+}
+
+function checkPrintPreviewClosed(aCallback) {
+  let count = 0;
+  executeSoon(function () {
+    if (!gInPrintPreviewMode) {
+      executeSoon(function () { aCallback(count < 1000); });
+      return;
+    }
+    if (++count == 1000) {
+      // The test might fail.
+      PrintUtils.exitPrintPreview();
+    }
+    executeSoon(arguments.callee);
+  });
+}