load mobile css/js files in native iOS/andorid apps and not mobile browsers

fixes: CNVS-29413

test plan:
* set up an account with new ui, and upload a 
  custom css/js 
* using something like postman,
  make an api request to a wiki page
* it should include a <link> to that css file
  and a <script> for that js file.

* make the same request from a mobile web browser
  (you can fake your user agent string in safari
  or chrome dev tools to fake this)
* it should not include that css or js file

Change-Id: I07493c8dc474231463cb1f97c0e07f2aad59ed0f
Reviewed-on: https://gerrit.instructure.com/79921
Reviewed-by: Simon Williams <simon@instructure.com>
Tested-by: Jenkins
QA-Review: Benjamin Christian Nelson <bcnelson@instructure.com>
Product-Review: Ryan Shaw <ryan@instructure.com>

app/jsx/theme_editor/ThemeEditor.jsx

@@ -442,13 +442,13 @@ define([
                       <div className="Theme__editor-upload-overrides">
 
                         <div className="Theme__editor-upload-overrides_header">
-                          { I18n.t('File(s) will be included when user content is displayed within Canvas iOS or Android apps.') }
+                          { I18n.t('File(s) will be included when user content is displayed within the Canvas iOS or Android apps, and in third-party apps built on our API.') }
                         </div>
 
                         <div className="Theme__editor-upload-overrides_form">
 
                           <ThemeEditorFileUpload
-                            label={I18n.t('Mobile CSS file')}
+                            label={I18n.t('Mobile app CSS file')}
                             accept=".css"
                             name="mobile_css_overrides"
                             currentValue={this.props.brandConfig.mobile_css_overrides}
@@ -457,7 +457,7 @@ define([
                           />
 
                           <ThemeEditorFileUpload
-                            label={I18n.t('Mobile JavaScript file')}
+                            label={I18n.t('Mobile app JavaScript file')}
                             accept=".js"
                             name="mobile_js_overrides"
                             currentValue={this.props.brandConfig.mobile_js_overrides}

lib/api.rb

@@ -508,7 +508,7 @@ module Api
 
     url_helper = Html::UrlProxy.new(self, context, host, protocol)
     account = Context.get_account(context) || @domain_root_account
-    include_mobile = respond_to?(:mobile_device?, true) && mobile_device?
+    include_mobile = !(respond_to?(:in_app?, true) && in_app?)
     Html::Content.rewrite_outgoing(html, account, url_helper, include_mobile: include_mobile)
   end
 

spec/lib/api_spec.rb

@@ -659,22 +659,39 @@ describe Api do
       expect(res).to eq html
     end
 
-    it 'prepends mobile css' do
+    context "mobile css/js" do
-      student_in_course
+      before(:each) do
-      account = @course.root_account
+        student_in_course
-      account.enable_feature!(:use_new_styles)
+        account = @course.root_account
-      bc = BrandConfig.create(mobile_css_overrides: 'somewhere.css')
+        account.enable_feature!(:use_new_styles)
-      account.brand_config_md5 = bc.md5
+        bc = BrandConfig.create(mobile_css_overrides: 'somewhere.css')
-      account.save!
+        account.brand_config_md5 = bc.md5
+        account.save!
 
-      html = "<p>a</p><p>b</p>"
+        @html = "<p>a</p><p>b</p>"
 
-      k = klass.new
+        @k = klass.new
-      k.stubs(:mobile_device?).returns(true)
+      end
-      res = k.api_user_content(html, @course, @student)
+
-      expect(res).to eq <<-HTML.strip
+      it 'prepends mobile css when not coming from a web browser' do
-<link rel="stylesheet" href="somewhere.css"><p>a</p><p>b</p>
+        res = @k.api_user_content(@html, @course, @student)
-      HTML
+        expect(res).to eq <<-HTML.strip
+  <link rel="stylesheet" href="somewhere.css"><p>a</p><p>b</p>
+        HTML
+      end
+
+      it 'does not prepend mobile css when coming from a web browser' do
+        @k.stubs(:in_app?).returns(true)
+        res = @k.api_user_content(@html, @course, @student)
+        expect(res).to eq "<p>a</p><p>b</p>"
+      end
+
+      it 'does not prepend mobile css when coming from a web browser, even if it is a mobile browser' do
+        @k.stubs(:in_app?).returns(true)
+        @k.stubs(:mobile_device?).returns(true)
+        res = @k.api_user_content(@html, @course, @student)
+        expect(res).to eq "<p>a</p><p>b</p>"
+      end
     end
   end