Remove useVanillaJNI flag and usage of fbjni in yoga build

Summary:
## Changelog:

[General] [Yoga] - Use vanilla jni instead of fbjni for all the jni communication

Reviewed By: astreet

Differential Revision: D17808005

fbshipit-source-id: 5e9a1ed73978f519c71c248774a28e5a294e7c7f

java/CMakeLists.txt

@@ -8,17 +8,14 @@ cmake_minimum_required(VERSION 3.4.1)
 set(CMAKE_VERBOSE_MAKEFILE on)
 
 # configure import libs
-set(libfb_DIR ${CMAKE_SOURCE_DIR}/../lib/fb/src/main/cpp)
 set(yogacore_DIR ${CMAKE_SOURCE_DIR}/..)
 
 set(build_DIR ${CMAKE_SOURCE_DIR}/build)
 
-set(libfb_build_DIR ${build_DIR}/libfb/${ANDROID_ABI})
 set(yogacore_build_DIR ${build_DIR}/yogacore/${ANDROID_ABI})
 
 file(MAKE_DIRECTORY ${build_DIR})
 
-add_subdirectory(${libfb_DIR} ${libfb_build_DIR})
 add_subdirectory(${yogacore_DIR} ${yogacore_build_DIR})
 
 add_compile_options(
@@ -36,7 +33,6 @@ file(GLOB jni_SRC
 add_library(yoga SHARED ${jni_SRC})
 
 target_include_directories(yoga PRIVATE
-    ${libfb_DIR}/include
     ${yogacore_DIR})
 
-target_link_libraries(yoga -Wl,--gc-sections yogacore fb)
+target_link_libraries(yoga -Wl,--gc-sections yogacore)