gn2bp: Add sysroot/usr/include to include

Test: ./update_result.sh
Change-Id: I5b6683d458ade7156d2e326826c38589474b3087
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index 0a73a19..da45395 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -851,6 +851,8 @@
         module.cpp_std = flag[len('-std='):]
       if '-isystem' in flag:
         module.local_include_dirs.add(flag[len('-isystem../../'):])
+      if '--sysroot' in flag:
+        module.local_include_dirs.add(flag[len('--sysroot=../../'):] + "/usr/include")
 
     # Adding local_include_dirs is necessary due to source_sets / filegroups
     # which do not properly propagate include directories.