Make clang work with ninja on Android.

build/android/envsetup.sh

 #!/bin/bash
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Sets up environment for building Chromium on Android.  It can either be
 # compiled with the Android tree or using the Android SDK/NDK. To build with
 # NDK/SDK: ". build/android/envsetup.sh --sdk".  Environment variable
 # ANDROID_SDK_BUILD=1 will then be defined and used in the rest of the setup to
@@ skipping 78 matching lines @@
 
 # Source a bunch of helper functions
 . ${CHROME_SRC}/build/android/adb_device_functions.sh
 
 ANDROID_GOMA_WRAPPER=""
 if [[ -d $GOMA_DIR ]]; then
   ANDROID_GOMA_WRAPPER="$GOMA_DIR/gomacc"
 fi
 export ANDROID_GOMA_WRAPPER
 
+# Declare Android are cross compile.
+export GYP_CROSSCOMPILE=1
+
 export CXX_target="${ANDROID_GOMA_WRAPPER} \
     $(echo -n ${ANDROID_TOOLCHAIN}/*-g++)"
 
 # Performs a gyp_chromium run to convert gyp->Makefile for android code.
 android_gyp() {
   echo "GYP_GENERATORS set to '$GYP_GENERATORS'"
   # http://crbug.com/143889.
   # In case we are doing a Clang build, we have to unset CC_target and
   # CXX_target. Otherwise GYP ends up generating a gcc build (although we set
   # 'clang' to 1). This behavior was introduced by
   # 54d2f6fe6d8a7b9d9786bd1f8540df6b4f46b83f in GYP.
   (
     # Fork to avoid side effects on the user's environment variables.
     if echo "$GYP_DEFINES" | grep -q clang; then
       if echo "$CXX_target" | grep -q g++; then
         unset CXX_target
       fi
     fi
     "${CHROME_SRC}/build/gyp_chromium" --depth="${CHROME_SRC}" --check "$@"
   )
 }
 
 # FLOCK needs to be null on system that has no flock
 which flock > /dev/null || export FLOCK=