Fix Mac ndk-build error on motive, pie_noon, pindrop.

We were looking for 'flatc' in motive/bin/Debug/flatc,
on Mac. It's actually built to flatbuffers/Debug/flatc.

Tested: OS X Yosemite, ndk-r10d. Also tested on Linux.
Change-Id: I9f1ecfe00c5f42fd9b6808b5a5da1c920487a4c2

.gitignore

@@ -39,8 +39,10 @@ tests/monsterdata_java_wire.mon
 tests/monsterdata_go_wire.mon
 CMakeLists.txt.user
 CMakeScripts/**
+CTestTestfile.cmake
 build/Xcode/FlatBuffers.xcodeproj/project.xcworkspace/**
 build/Xcode/FlatBuffers.xcodeproj/xcuserdata/**
+FlatBuffers.xcodeproj/
 java/.idea
 java/*.iml
 java/target

android/jni/include.mk

@@ -49,15 +49,20 @@ endif
 # The following block generates build rules which result in headers being
 # rebuilt from flatbuffers schemas.
 
+FLATBUFFERS_CMAKELISTS_DIR := \
+  $(realpath $(dir $(lastword $(MAKEFILE_LIST)))/../..)
+
 # Directory that contains the FlatBuffers compiler.
-FLATBUFFERS_FLATC_PATH?=$(CURDIR)/bin
 ifeq (Windows,$(PROJECT_OS))
+FLATBUFFERS_FLATC_PATH?=$(CURDIR)/bin
 FLATBUFFERS_FLATC := $(FLATBUFFERS_FLATC_PATH)/Debug/flatc.exe
 endif
 ifeq (Linux,$(PROJECT_OS))
+FLATBUFFERS_FLATC_PATH?=$(CURDIR)/bin
 FLATBUFFERS_FLATC := $(FLATBUFFERS_FLATC_PATH)/flatc
 endif
 ifeq (Darwin,$(PROJECT_OS))
+FLATBUFFERS_FLATC_PATH?=$(FLATBUFFERS_CMAKELISTS_DIR)
 FLATBUFFERS_FLATC := $(FLATBUFFERS_FLATC_PATH)/Debug/flatc
 endif
 
@@ -80,8 +85,6 @@ CMAKE := cmake
 endif
 
 # Generate a host build rule for the flatbuffers compiler.
-FLATBUFFERS_CMAKELISTS_DIR := \
-  $(realpath $(dir $(lastword $(MAKEFILE_LIST)))/../..)
 ifeq (Windows,$(PROJECT_OS))
 define build_flatc_recipe
 	cd  & jni\build_flatc.bat $(CMAKE)