Update V8 DEPS.

Makefile.android

Index: Makefile.android
diff --git a/Makefile.android b/Makefile.android
index f89fd21fda004ea1bac07d5f119b1e837b5ac8ab..d781d92d38b073f792d73f29654b7fd735d6b9fb 100644
--- a/Makefile.android
+++ b/Makefile.android
@@ -46,7 +46,7 @@ else
 endif
 
 ifeq ($(ARCH), android_arm)
-  DEFINES  = target_arch=arm v8_target_arch=arm android_target_arch=arm android_target_platform=14
+  DEFINES  = target_arch=arm v8_target_arch=arm android_target_arch=arm android_target_platform=21
   DEFINES += arm_neon=0 arm_version=7
   TOOLCHAIN_ARCH = arm-linux-androideabi
   TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
@@ -57,13 +57,13 @@ else ifeq ($(ARCH), android_arm64)
   TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
   TOOLCHAIN_VER = 4.9
 else ifeq ($(ARCH), android_mipsel)
-  DEFINES  = target_arch=mipsel v8_target_arch=mipsel android_target_platform=14
+  DEFINES  = target_arch=mipsel v8_target_arch=mipsel android_target_platform=21
   DEFINES += android_target_arch=mips mips_arch_variant=mips32r2
   TOOLCHAIN_ARCH = mipsel-linux-android
   TOOLCHAIN_PREFIX = $(TOOLCHAIN_ARCH)
   TOOLCHAIN_VER = 4.8
 else ifeq ($(ARCH), android_ia32)
-  DEFINES = target_arch=ia32 v8_target_arch=ia32 android_target_arch=x86 android_target_platform=14
+  DEFINES = target_arch=ia32 v8_target_arch=ia32 android_target_arch=x86 android_target_platform=21
   TOOLCHAIN_ARCH = x86
   TOOLCHAIN_PREFIX = i686-linux-android
   TOOLCHAIN_VER = 4.8
@@ -73,7 +73,7 @@ else ifeq ($(ARCH), android_x64)
   TOOLCHAIN_PREFIX = x86_64-linux-android
   TOOLCHAIN_VER = 4.9
 else ifeq ($(ARCH), android_x87)
-  DEFINES = target_arch=x87 v8_target_arch=x87 android_target_arch=x86 android_target_platform=14
+  DEFINES = target_arch=x87 v8_target_arch=x87 android_target_arch=x86 android_target_platform=21
   TOOLCHAIN_ARCH = x86
   TOOLCHAIN_PREFIX = i686-linux-android
   TOOLCHAIN_VER = 4.8