Moving Pause button to the left of the context menu header

See this mock:
https://www.google.com/url?q=https://docs.google.com/presentation/d/1AepsnLeKcRhjMW35SkB5yMKO3u6waigug8Tyfe0LO5o/edit%23slide%3Did.g455d187f2a_0_45&sa=D&ust=1542320415002000&usg=AFQjCNH-jsy5THG1WqxjeYbj628QFMJKvQ

Bug: 117888000
Test: Manual
Change-Id: I1edbc569347f09f0806ad6749735c3dec198277a

res/layout/system_shortcut_icons.xml

@@ -22,4 +22,10 @@
     android:orientation="horizontal"
     android:gravity="end|center_vertical"
     android:background="?attr/popupColorSecondary"
-    android:clipToPadding="true" />
+    android:clipToPadding="true">
+
+    <Space android:layout_width="0dp"
+           android:layout_height="match_parent"
+           android:layout_weight="1"
+           android:id="@+id/separator"/>
+</LinearLayout>

src/com/android/launcher3/popup/ArrowPopup.java

@@ -126,6 +126,12 @@ public abstract class ArrowPopup extends AbstractFloatingView {
         return (T) view;
     }
 
+    public <T extends View> T inflateAndAdd(int resId, ViewGroup container, int index) {
+        View view = mInflater.inflate(resId, container, false);
+        container.addView(view, index);
+        return (T) view;
+    }
+
     /**
      * Called when all view inflation and reordering in complete.
      */

src/com/android/launcher3/popup/PopupContainerWithArrow.java

@@ -391,7 +391,8 @@ public class PopupContainerWithArrow extends ArrowPopup implements DragSource,
     }
 
     private void initializeSystemShortcut(int resId, ViewGroup container, SystemShortcut info) {
-        View view = inflateAndAdd(resId, container);
+        View view = inflateAndAdd(
+                resId, container, getInsertIndexForSystemShortcut(container, info));
         if (view instanceof DeepShortcutView) {
             // Expanded system shortcut, with both icon and text shown on white background.
             final DeepShortcutView shortcutView = (DeepShortcutView) view;
@@ -405,6 +406,17 @@ public class PopupContainerWithArrow extends ArrowPopup implements DragSource,
                 (ItemInfo) mOriginalIcon.getTag()));
     }
 
+    /**
+     * Returns an index for inserting a shortcut into a container.
+     */
+    private int getInsertIndexForSystemShortcut(ViewGroup container, SystemShortcut shortcut) {
+        final View separator = container.findViewById(R.id.separator);
+
+        return separator != null && shortcut.isLeftGroup() ?
+                container.indexOfChild(separator) :
+                container.getChildCount();
+    }
+
     /**
      * Determines when the deferred drag should be started.
      *

src/com/android/launcher3/popup/RemoteActionShortcut.java

@@ -76,4 +76,9 @@ public class RemoteActionShortcut extends SystemShortcut<Launcher> {
                     LauncherLogProto.ControlType.REMOTE_ACTION_SHORTCUT, view);
         };
     }
+
+    @Override
+    public boolean isLeftGroup() {
+        return true;
+    }
 }

src/com/android/launcher3/popup/SystemShortcut.java

@@ -71,6 +71,13 @@ public abstract class SystemShortcut<T extends BaseDraggingActivity> extends Ite
         mAccessibilityActionId = other.mAccessibilityActionId;
     }
 
+    /**
+     * Should be in the left group of icons in app's context menu header.
+     */
+    public boolean isLeftGroup() {
+        return false;
+    }
+
     public void setIconAndLabelFor(View iconView, TextView labelView) {
         if (mIcon != null) {
             mIcon.loadDrawableAsync(iconView.getContext(),