Move password-related methods from core.js to password_controller.js.

ios/chrome/browser/passwords/resources/password_controller.js

Index: ios/chrome/browser/passwords/resources/password_controller.js
diff --git a/ios/chrome/browser/passwords/resources/password_controller.js b/ios/chrome/browser/passwords/resources/password_controller.js
index f3bb4213d9097e437d8dd52d3c0753e3b917288e..b8b9fb5b74df005ec20a11861ed8e51b68d5c1ba 100644
--- a/ios/chrome/browser/passwords/resources/password_controller.js
+++ b/ios/chrome/browser/passwords/resources/password_controller.js
@@ -28,13 +28,55 @@ if (__gCrWeb && !__gCrWeb['fillPasswordForm']) {
    */
   __gCrWeb['findPasswordForms'] = function() {
     var formDataList = [];
-    if (__gCrWeb.hasPasswordField()) {
+    if (hasPasswordField_(window)) {
       __gCrWeb.getPasswordFormDataList(formDataList, window);
     }
     return __gCrWeb.stringify(formDataList);
   };
 
   /**
+   * Returns true if the top window or any frames inside contain an input field
+   * of type 'password'. This method is only used for unit tests and are only
+   * kept for legacy reasons. Prefer to use the private
+   * {@code hasPasswordField_} within this file.
+   * @return {boolean} Whether a password field exists.
+   *
+   * TODO(danyao): investigate if this method can be completely removed from the

[Eugene But (OOO till 7-30), 2017/04/11 16:19:40]

Per Google's Unit Testing Best Practices: "Test code using real APIs - don’t
define back doors only for tests.". go/unit-test-practices?cl=head#public-apis

Should we keep this method public (w/o TestOnly suffix) until there is a better
way to test the code?

[Eugene But (OOO till 7-30), 2017/04/11 16:19:40]

In Chrome for iOS we use |TODO(crbug.com/<bug number>)| format, because when
people leave comments don't get updated :)

[danyao, 2017/04/11 18:05:06]

Done. This seems too small to warrant its own bug. I've added crbug.com/614092
here and will investigate right away after this CL.

[danyao, 2017/04/11 18:05:06]

Done.

+   * gCrWeb public interface.
+   */
+  __gCrWeb['hasPasswordFieldTestOnly'] = function() {
+    return hasPasswordField_(window);
+  };
+
+  /** Returns true if the supplied window or any frames inside contain an input
+   * field of type 'password'.
+   * @private
+   */
+  var hasPasswordField_ = function(win) {
+    var doc = win.document;
+
+    // We may will not be allowed to read the 'document' property from a frame
+    // that is in a different domain.
+    if (!doc) {
+      return false;
+    }
+
+    if (doc.querySelector('input[type=password]')) {
+      return true;
+    }
+
+    var frames = win.frames;
+    for (var i = 0; i < frames.length; i++) {
+      if (hasPasswordField_(frames[i])) {
+        return true;
+      }
+    }
+
+    return false;
+  };
+
+
+  /**
    * Returns the password form with the given |name| as a JSON string.
    * @param {string} name The name of the form to extract.
    * @return {string} The password form.