Add skeleton implementations for gesture

Change-Id: I169034eba2001b98bad8f8a05372426c3ff8774e
diff --git a/native/jni/Android.mk b/native/jni/Android.mk
index a6bb487..0b73fc9 100644
--- a/native/jni/Android.mk
+++ b/native/jni/Android.mk
@@ -28,6 +28,7 @@
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(LATIN_IME_SRC_DIR)
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(LATIN_IME_SRC_DIR)/gesture
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(LATIN_IME_SRC_DIR)/gesture/impl
+LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(LATIN_IME_SRC_DIR)/gesture/impl/header
 
 LOCAL_CFLAGS += -Werror -Wall
 
@@ -50,7 +51,11 @@
     proximity_info.cpp \
     proximity_info_state.cpp \
     unigram_dictionary.cpp \
-    gesture/build_check.cpp
+    gesture/build_check.cpp \
+    gesture/impl/gesture_decoder_impl.cpp \
+    gesture/impl/incremental_decoder_impl.cpp \
+    gesture/impl/token_beam_impl.cpp \
+    gesture/impl/token_impl.cpp
 
 LOCAL_SRC_FILES := \
     $(LATIN_IME_JNI_SRC_FILES) \