Added a test that currently is able to print to pdf.

chrome/browser/resources/print_preview/native_layer.js

Index: chrome/browser/resources/print_preview/native_layer.js
diff --git a/chrome/browser/resources/print_preview/native_layer.js b/chrome/browser/resources/print_preview/native_layer.js
index efdd55b36073695ca5a34c475a299e408e7ea0a9..522915110a475a9abb82a6c9480178b75f0b76d1 100644
--- a/chrome/browser/resources/print_preview/native_layer.js
+++ b/chrome/browser/resources/print_preview/native_layer.js
@@ -46,6 +46,9 @@ cr.define('print_preview', function() {
     global['onPrivetCapabilitiesSet'] =
         this.onPrivetCapabilitiesSet_.bind(this);
     global['onPrivetPrintFailed'] = this.onPrivetPrintFailed_.bind(this);
+    global['onEnableManipulateSettings'] =

[ivandavid, 2014/06/17 22:59:16]

Allows the native layer to send a message to print_preview that we are in a
testing environment which needs to actually manipulate the print preview
settings. That way, print preview should work with my changes in a non-testing
environment because it will no longer automatically send an uncaught message
(specifically the message sent by onPreviewGenerationDone).

+        this.onEnableManipulateSettings_.bind(this);
+    //global['onManipulateSettings'] = this.onManipulateSettings_.bind(this);
   };
 
   /**
@@ -77,7 +80,8 @@ cr.define('print_preview', function() {
     PRIVET_PRINTER_CHANGED: 'print_preview.NativeLayer.PRIVET_PRINTER_CHANGED',
     PRIVET_CAPABILITIES_SET:
         'print_preview.NativeLayer.PRIVET_CAPABILITIES_SET',
-    PRIVET_PRINT_FAILED: 'print_preview.NativeLayer.PRIVET_PRINT_FAILED'
+    PRIVET_PRINT_FAILED: 'print_preview.NativeLayer.PRIVET_PRINT_FAILED',
+    MANIPULATE_SETTINGS: 'print_preview.NativeLayer.MANIPULATE_SETTINGS'
   };
 
   /**
@@ -672,6 +676,49 @@ cr.define('print_preview', function() {
             new Event(NativeLayer.EventType.PRIVET_PRINT_FAILED);
       privetPrintFailedEvent.httpError = http_error;
       this.dispatchEvent(privetPrintFailedEvent);
+    },
+
+    /**
+     * Function that allows for onManipulateSettings to be called
+     * from the native layer, specifically during testing.

[Lei Zhang, 2014/06/17 23:22:20]

specifically -> only? Maybe onEnableManipulateSettings can have test or testing
in the name it's obvious.

+     */
+    onEnableManipulateSettings_: function() {

[ivandavid, 2014/06/17 22:59:16]

See comment for line 49.

+      global['onManipulateSettings'] =
+          this.onManipulateSettings_.bind(this);
+    },
+
+    /**
+     * Function call from browsertest to start clicking certain buttons.
+     * @param {string} messageName The setting that is to be manipulated,
+     *    such as the layout settings, or page numbers
+     * @param {string, boolean, undefined} Is the value that we want to
+     *    set the particular setting to. For layout settings, page numbers,
+     *    and margins, its a string. For 'headers and footers' and
+     *    'background colors and images,' its a boolean. For Save as PDF,
+     *    its undefined as it isn't needed.
+     */
+    onManipulateSettings_: function(messageName, parameter) {
+      var manipulateSettingsEvent =
+          new Event(NativeLayer.EventType.MANIPULATE_SETTINGS);
+      manipulateSettingsEvent.messageName = messageName;
+      if (messageName == 'SAVE_AS_PDF') {
+      }
+      else if (messageName == 'LAYOUT_SETTINGS') {
+        manipulateSettingsEvent.layoutSettings = parameter;
+      }
+      else if (messageName == 'PAGE_NUMBERS') {
+        manipulateSettingsEvent.pageNumbers = parameter;
+      }
+      else if (messageName == 'HEADERS_AND_FOOTERS') {
+        manipulateSettingsEvent.headersAndFooters = parameter;
+      }
+      else if (messageName == 'BACKGROUND_COLORS_AND_IMAGES') {
+        manipulateSettingsEvent.backgroundColorsAndImages = parameter;
+      }
+      else if (messageName == 'MARGINS') {
+        manipulateSettingsEvent.margins = parameter;
+      }
+      this.dispatchEvent(manipulateSettingsEvent);
     }
   };