Remove ExactCalculator module

Individual products can add their own calculator package if desired.

Bug: 120905067
Test: lunch aosp_arm64 && make -j8
Merged-In: I60490b6e2a42c4304768075e8fef9f07cb72d268
Change-Id: I60490b6e2a42c4304768075e8fef9f07cb72d268
diff --git a/CleanSpec.mk b/CleanSpec.mk
index b06a87b..b32868e 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -529,6 +529,9 @@
 $(call add-clean-step, find system/app system/priv-app system/framework system_other -depth -type d -print0 | xargs -0 rmdir)
 $(call add-clean-step, rm -f .d)
 
+# Remove obsolete apps
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/*)
+
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************