adding some small changes to support android build,

mainly cmake stuff, but in persistance the wcstombs
is not supported on android, and in
sift.cpp there was and ifdef that affected arm and this
causes undefined symbols on android.

modules/highgui/CMakeLists.txt

@@ -3,6 +3,7 @@
 #   Some parts taken from version of Hartmut Seichter, HIT Lab NZ.
 #   Jose Luis Blanco, 2008
 # ----------------------------------------------------------------------------
+if(!ANDROID)
 project(opencv_highgui)
 
 if(WITH_JPEG)
@@ -332,3 +333,21 @@ install(TARGETS ${the_target}
 install(FILES ${highgui_ext_hdrs}
         DESTINATION include/opencv2/highgui
         COMPONENT main)
+        
+else(!ANDROID)
+set(high_gui_android_srcs src/bitstrm.cpp
+    src/cap.cpp 
+    src/grfmt_base.cpp 
+    src/grfmt_bmp.cpp 
+    src/grfmt_jpeg.cpp
+    src/grfmt_jpeg2000.cpp
+    src/grfmt_png.cpp 
+    src/grfmt_tiff.cpp 
+    src/loadsave.cpp 
+    src/precomp.cpp 
+    src/utils.cpp 
+    src/grfmt_sunras.cpp 
+    src/grfmt_pxm.cpp 
+    src/window.cpp )
+define_android_manual(highgui "${high_gui_android_srcs}" "$(LOCAL_PATH)/src  $(OPENCV_INCLUDES)")	
+endif(!ANDROID)