Enable Error Prone to detect obscure bugs.

We've been writing many new framework-specific Error Prone checkers
to help detect obscure platform bugs, and this change starts enabling
those checkers for more packages across the platform.

Bug: 155703208
Test: manual
Exempt-From-Owner-Approval: trivial blueprint changes
Change-Id: I1db3412b0be40f6f78c68331ae01756887192071
diff --git a/packages/InputDevices/Android.bp b/packages/InputDevices/Android.bp
index 7532aea..5afbe72 100644
--- a/packages/InputDevices/Android.bp
+++ b/packages/InputDevices/Android.bp
@@ -14,6 +14,7 @@
 
 android_app {
     name: "InputDevices",
+    defaults: ["platform_app_defaults"],
 
     srcs: [
         "**/*.java",