Add FIXME comments for layout performance and simplification

Author: MihaiCristianCondrea

app/src/main/res/layout/activity_shortcuts_navigation_and_searching.xml

@@ -6,6 +6,8 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent">
 
+    <!-- FIXME: `activity_shortcuts_navigation_and_searching.xml` has more than 80 views, bad for performance-->
+
     <me.zhanghai.android.fastscroll.FastScrollScrollView
         android:id="@+id/scroll_view"
         android:layout_width="0dp"

app/src/main/res/layout/item_android_studio_category.xml

@@ -7,6 +7,8 @@
     android:orientation="horizontal"
     android:padding="16dp">
 
+    <!-- FIXME: This tag and its children can be replaced by one `<TextView/>` and a compound drawable-->
+
     <ImageView
         android:id="@+id/category_icon"
         android:layout_width="24dp"