Revert "Clear All button added in  Recent Panelview."

This reverts commit 66ff5222f3da3f49bdf6990e95648d984f08cd10.

Conflicts:
	packages/SystemUI/res/layout-land/status_bar_recent_panel.xml
	packages/SystemUI/res/layout/status_bar_recent_panel.xml
	packages/SystemUI/src/com/android/systemui/recent/RecentsPanelView.java