Moving SysUI with legacy Recents to another build target

- Move all legacy recents code out of the core sysui code
- Add separate target for products which still depend on it
- Move overview proxy implementation into another implementation of the
  recents interface

Test: atest SystemUITests
Test: Push SystemUiWithLegacyRecents to the system image
      adb shell pm disable com.google.android.apps.nexuslauncher/com.android.quickstep.TouchInteractionService
      and ensure that the old recents implementation still works (and split
      screen)

Change-Id: Iad67218ec37c13c79b6393d87f6bdc4f3996e2c6
Signed-off-by: Winson Chung <winsonc@google.com>
diff --git a/packages/SystemUI/legacy/recents/proguard.flags b/packages/SystemUI/legacy/recents/proguard.flags
new file mode 100644
index 0000000..c358949
--- /dev/null
+++ b/packages/SystemUI/legacy/recents/proguard.flags
@@ -0,0 +1,14 @@
+-keepclassmembers class ** {
+    public void onBusEvent(**);
+    public void onInterprocessBusEvent(**);
+}
+-keepclassmembers class ** extends **.EventBus$InterprocessEvent {
+    public <init>(android.os.Bundle);
+}
+
+-keep class com.android.systemui.recents.views.TaskView {
+    public int getDim();
+    public void setDim(int);
+    public float getTaskProgress();
+    public void setTaskProgress(float);
+}
\ No newline at end of file