c2_e2e_test: lower sdk version

Lower sdk version so APK can be installed on P.

Test: build & install APK in ARC++ P
Bug: 136142167

Change-Id: Ie628c927715eaa7307ba5e175399707f28d37de7

tests/c2_e2e_test/Android.mk

@@ -6,7 +6,7 @@ LOCAL_PATH := $(call my-dir)
 
 include $(CLEAR_VARS)
 
-LOCAL_SDK_VERSION := current
+LOCAL_SDK_VERSION := 26
 
 LOCAL_SRC_FILES := \
     $(call all-java-files-under, src) \