Add skeleton implementation for Attention API

This service will let the system know whether the user is paying attention to
the device. This may be useful in certain scenarios - like keeping the screen
on, even when there has been no touch related user activity.

New permission BIND_ATTENTION_SERVICE is added to ensure that only the system
can bind to the attention service.

Test: manually tested the lifecycle is as expected
Bug: 111939367
Change-Id: I2dab9c69f3d0c6efb0db572f797f517dc6efcc72
diff --git a/Android.bp b/Android.bp
index c202408..38d8649 100644
--- a/Android.bp
+++ b/Android.bp
@@ -357,6 +357,8 @@
         "core/java/android/service/textclassifier/ITextLanguageCallback.aidl",
         "core/java/android/service/textclassifier/ITextLinksCallback.aidl",
         "core/java/android/service/textclassifier/ITextSelectionCallback.aidl",
+        "core/java/android/service/attention/IAttentionService.aidl",
+        "core/java/android/service/attention/IAttentionCallback.aidl",
         "core/java/android/view/accessibility/IAccessibilityInteractionConnection.aidl",
         "core/java/android/view/accessibility/IAccessibilityInteractionConnectionCallback.aidl",
         "core/java/android/view/accessibility/IAccessibilityManager.aidl",