Bug 1387644 - Return NoSuchElementError when element is not found r=ato

MozReview-Commit-ID: LDHiyce09GR

--HG--
extra : rebase_source : dff3b50237a3d124c0c41458c0adaf94694f45ef

testing/marionette/element.js

@@ -161,7 +161,7 @@ element.Store = class {
    * @returns {nsIDOMElement}
    *     Element associated with reference.
    *
-   * @throws {JavaScriptError}
+   * @throws {NoSuchElementError}
    *     If the provided reference is unknown.
    * @throws {StaleElementReferenceError}
    *     If element has gone stale, indicating it is no longer attached to
@@ -170,7 +170,8 @@ element.Store = class {
   get(uuid, container) {
     let el = this.els[uuid];
     if (!el) {
-      throw new JavaScriptError(`Element reference not seen before: ${uuid}`);
+      throw new NoSuchElementError(`Element reference not seen before: ` +
+                                   `${uuid}`);
     }
 
     try {

testing/marionette/harness/marionette_harness/tests/unit/test_screenshot.py

@@ -9,7 +9,7 @@ import struct
 import urllib
 
 from marionette_driver import By
-from marionette_driver.errors import JavascriptException, NoSuchWindowException
+from marionette_driver.errors import NoSuchElementException, NoSuchWindowException
 from marionette_harness import (
     MarionetteTestCase,
     skip,
@@ -275,12 +275,12 @@ class TestScreenCaptureChrome(WindowManagerMixin, ScreenCaptureTestCase):
             self.marionette.navigate(box)
             content_element = self.marionette.find_element(By.ID, "green")
 
-        self.assertRaisesRegexp(JavascriptException, "Element reference not seen before",
+        self.assertRaisesRegexp(NoSuchElementException, "Element reference not seen before",
                                 self.marionette.screenshot, highlights=[content_element])
 
         chrome_document_element = self.document_element
         with self.marionette.using_context('content'):
-            self.assertRaisesRegexp(JavascriptException, "Element reference not seen before",
+            self.assertRaisesRegexp(NoSuchElementException, "Element reference not seen before",
                                     self.marionette.screenshot,
                                     highlights=[chrome_document_element])