Remove the search icon from the search box in the experimental app list.

This CL removes the magnifying glass icon from the experimental app
list. The normal app list should be unaffected

BUG=406222

Review URL: https://codereview.chromium.org/503693002

Cr-Commit-Position: refs/heads/master@{#292569}

ui/app_list/views/search_box_view.cc

@@ -83,13 +83,16 @@ SearchBoxView::SearchBoxView(SearchBoxViewDelegate* delegate,
     : delegate_(delegate),
       view_delegate_(view_delegate),
       model_(NULL),
-      icon_view_(new views::ImageView),
+      icon_view_(NULL),
       speech_button_(NULL),
       search_box_(new views::Textfield),
       contents_view_(NULL) {
-  AddChildView(icon_view_);
-  if (switches::IsExperimentalAppListEnabled())
+  if (switches::IsExperimentalAppListEnabled()) {
     set_background(new SearchBoxBackground());
+  } else {
+    icon_view_ = new views::ImageView;
+    AddChildView(icon_view_);
+  }
 
   views::BoxLayout* layout = new views::BoxLayout(
       views::BoxLayout::kHorizontal, kPadding, 0, kPadding);
@@ -219,7 +222,8 @@ void SearchBoxView::OnMenuButtonClicked(View* source, const gfx::Point& point) {
 }
 
 void SearchBoxView::IconChanged() {
-  icon_view_->SetImage(model_->search_box()->icon());
+  if (icon_view_)
+    icon_view_->SetImage(model_->search_box()->icon());
 }
 
 void SearchBoxView::SpeechRecognitionButtonPropChanged() {