[Android] Add arm64 target to gyp_webview

android_webview/tools/gyp_webview

Index: android_webview/tools/gyp_webview
diff --git a/android_webview/tools/gyp_webview b/android_webview/tools/gyp_webview
index 4f7c2d88650795a92ffb9288e3e2a8ef497f8821..96601475dff20e3a7df5e64a5362f9b1e807547a 100755
--- a/android_webview/tools/gyp_webview
+++ b/android_webview/tools/gyp_webview
@@ -65,6 +65,9 @@ for host_os in linux mac; do
   if [ "$PLATFORM" == "${host_platform}-arm" -o "$PLATFORM" == "all" ]; then
     ${GYP} --suffix .${host_platform}-arm ${EFLAGS} -Dtarget_arch=arm
   fi
+  if [ "$PLATFORM" == "${host_platform}-arm64" -o "$PLATFORM" == "all" ]; then
+    ${GYP} --suffix .${host_platform}-arm64 ${EFLAGS} -Dtarget_arch=arm64
+  fi
   if [ "$PLATFORM" == "${host_platform}-x86" -o "$PLATFORM" == "all" ]; then
     ${GYP} --suffix .${host_platform}-x86 ${EFLAGS} -Dtarget_arch=ia32
   fi