Fixes std::thread not working with clang compiler on Android in NDK r8/r9.

gameplay/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_MODULES := libgameplay

samples/browser/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

samples/character/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

samples/lua/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

samples/mesh/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

samples/particles/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

samples/racer/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

samples/spaceship/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a

template/android/jni/Application.mk

@@ -1,4 +1,4 @@
-NDK_TOOLCHAIN_VERSION := clang
+NDK_TOOLCHAIN_VERSION := 4.8
 APP_CPPFLAGS += -std=c++11
 APP_STL     := gnustl_static
 APP_ABI     := armeabi-v7a