Merge java-overridable/ into java/ again

This CL a logical revert of a previous CL [1], which separated Java
files into common ones and overridable ones.  Now that that overriding
concept is no longer used, there is no need to keep having separate
directory structure.

 [1]: Ic734bd4d20aa050c688a3158b1a382ae0ac18991
      fb74ab15c1343084740d65ef8744cad33a678e82

Fix: 79323502
Test: make -j aosp_taimen-userdebug && make -j
Test: tapas LatinIME && make -j
Change-Id: I2090bc25d18e6d4f24e91c2cbfe832755cbb4e8f
diff --git a/java/Android.mk b/java/Android.mk
index 154f3a2..837b2d9 100644
--- a/java/Android.mk
+++ b/java/Android.mk
@@ -17,7 +17,7 @@
 
 LOCAL_MODULE_TAGS := optional
 
-LOCAL_SRC_FILES := $(call all-java-files-under, src ../java-overridable/src)
+LOCAL_SRC_FILES := $(call all-java-files-under, src)
 
 LOCAL_PACKAGE_NAME := LatinIME