Fix LOCAL_CPP_EXTENSION.

Bug: 28622149
Change-Id: I785b9bdf90f77ed87c41542f3bd010c6b7356069
(cherry picked from commit 070b6199012eaf0c962f2ff4313551b13735198d)
diff --git a/perfprofd/Android.mk b/perfprofd/Android.mk
index 99d6c66..6409f83 100644
--- a/perfprofd/Android.mk
+++ b/perfprofd/Android.mk
@@ -12,7 +12,7 @@
 #
 include $(CLEAR_VARS)
 LOCAL_CLANG := true
-LOCAL_CPP_EXTENSION := cc
+LOCAL_CPP_EXTENSION := .cc
 LOCAL_MODULE := libperfprofdcore
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_MODULE_PATH := $(TARGET_OUT_OPTIONAL_EXECUTABLES)
@@ -41,7 +41,7 @@
 #
 include $(CLEAR_VARS)
 LOCAL_CLANG := true
-LOCAL_CPP_EXTENSION := cc
+LOCAL_CPP_EXTENSION := .cc
 LOCAL_CXX_STL := libc++
 LOCAL_MODULE := libperfprofdutils
 LOCAL_MODULE_PATH := $(TARGET_OUT_OPTIONAL_EXECUTABLES)
@@ -55,7 +55,7 @@
 #
 include $(CLEAR_VARS)
 LOCAL_CLANG := true
-LOCAL_CPP_EXTENSION := cc
+LOCAL_CPP_EXTENSION := .cc
 LOCAL_CXX_STL := libc++
 LOCAL_SRC_FILES := perfprofdmain.cc
 LOCAL_STATIC_LIBRARIES := libperfprofdcore libperfprofdutils
diff --git a/perfprofd/tests/Android.mk b/perfprofd/tests/Android.mk
index 7d372c4..bdd82e0 100644
--- a/perfprofd/tests/Android.mk
+++ b/perfprofd/tests/Android.mk
@@ -8,7 +8,7 @@
 #
 include $(CLEAR_VARS)
 LOCAL_CLANG := true
-LOCAL_CPP_EXTENSION := cc
+LOCAL_CPP_EXTENSION := .cc
 LOCAL_CXX_STL := libc++
 LOCAL_C_INCLUDES += system/extras/perfprofd
 LOCAL_MODULE := libperfprofdmockutils
@@ -32,7 +32,7 @@
 #
 include $(CLEAR_VARS)
 LOCAL_CLANG := true
-LOCAL_CPP_EXTENSION := cc
+LOCAL_CPP_EXTENSION := .cc
 LOCAL_CXX_STL := libc++
 LOCAL_STATIC_LIBRARIES := libperfprofdcore libperfprofdmockutils libgtest libbase
 LOCAL_SHARED_LIBRARIES := libprotobuf-cpp-lite