NUX Onboarding: create landing page skeleton.

This CL also adds a helper function to check if the NUX onboarding feature
should be force-enabled on non-win/non-branded builds. This will make
testing and development for the feature much easier. There will be follow-up
CLs to transition all NUX contents to be behind this flag instead of the
build flags.

To test this, add --enable-features=NuxOnboardingForceEnabled

Bug: 874142
Change-Id: I0c1ae6d396901b0a7cbb1c13fe158b488ff0e14c
Reviewed-on: https://chromium-review.googlesource.com/1229502
Reviewed-by: Hector Carmona <[email protected]>
Reviewed-by: Demetrios Papadopoulos <[email protected]>
Commit-Queue: Scott Chen <[email protected]>
Cr-Commit-Position: refs/heads/master@{#593017}
diff --git a/chrome/browser/ui/webui/welcome_ui.cc b/chrome/browser/ui/webui/welcome_ui.cc
index 5bade86..aa732e7 100644
--- a/chrome/browser/ui/webui/welcome_ui.cc
+++ b/chrome/browser/ui/webui/welcome_ui.cc
@@ -10,6 +10,7 @@
 #include "build/build_config.h"
 #include "chrome/browser/favicon/favicon_service_factory.h"
 #include "chrome/browser/signin/account_consistency_mode_manager.h"
+#include "chrome/browser/ui/webui/welcome/nux_helper.h"
 #include "chrome/browser/ui/webui/welcome_handler.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/browser_resources.h"
@@ -68,9 +69,18 @@
   html_source->AddResourcePath("logo.png", IDR_PRODUCT_LOGO_128);
   html_source->AddResourcePath("logo2x.png", IDR_PRODUCT_LOGO_256);
 
-  // Use special layout if the application is branded and DICE is enabled.
-  // Otherwise use the default layout.
-  if (kIsBranded && is_dice) {
+  if (nux::IsNuxOnboardingEnabled()) {
+    // Add Onboarding welcome strings.
+    html_source->AddLocalizedString("headerText", IDS_WELCOME_HEADER);
+
+    // Add onboarding welcome resources.
+    // TODO(scottchen): More resources to be added here.
+    html_source->SetDefaultResource(
+        IDR_WELCOME_ONBOARDING_WELCOME_WELCOME_HTML);
+
+  } else if (kIsBranded && is_dice) {
+    // Use special layout if the application is branded and DICE is enabled.
+    // Otherwise use the default layout.
     html_source->AddLocalizedString("headerText", IDS_WELCOME_HEADER);
     html_source->AddLocalizedString("secondHeaderText",
                                     IDS_DICE_WELCOME_SECOND_HEADER);