Remove global include paths for modules built against NDK

Modules built against the NDK shouldn't get the global or arch-specific
include paths, all headers will be provided by depenendencies or the
NDK.

Change-Id: I13b9530a365e11e9cf6bd2b99b756b36944e0a9e
diff --git a/cc/cc.go b/cc/cc.go
index 18e499d..594ae25 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -451,7 +451,7 @@
 			common.ModuleGenDir(ctx),
 		}...)
 
-		if c.properties.Sdk_version == "" {
+		if c.properties.Sdk_version == "" || ctx.Host() {
 			flags.IncludeDirs = append(flags.IncludeDirs, "${SrcDir}/libnativehelper/include/nativehelper")
 		}
 
@@ -459,26 +459,26 @@
 			flags.LdFlags = append(flags.LdFlags, "-Wl,--no-undefined")
 		}
 
+		if ctx.Host() || c.properties.Sdk_version == "" {
+			flags.GlobalFlags = append(flags.GlobalFlags,
+				"${commonGlobalIncludes}",
+				toolchain.IncludeFlags())
+		}
+
+		flags.GlobalFlags = append(flags.GlobalFlags, instructionSetFlags)
+
 		if flags.Clang {
 			flags.CppFlags = append(flags.CppFlags, "${commonClangGlobalCppflags}")
-			flags.GlobalFlags = []string{
-				"${commonGlobalIncludes}",
-				toolchain.IncludeFlags(),
-				instructionSetFlags,
+			flags.GlobalFlags = append(flags.GlobalFlags,
 				toolchain.ClangCflags(),
 				"${commonClangGlobalCflags}",
-				fmt.Sprintf("${%sClangGlobalCflags}", ctx.Arch().HostOrDevice),
-			}
+				fmt.Sprintf("${%sClangGlobalCflags}", ctx.Arch().HostOrDevice))
 		} else {
 			flags.CppFlags = append(flags.CppFlags, "${commonGlobalCppflags}")
-			flags.GlobalFlags = []string{
-				"${commonGlobalIncludes}",
-				toolchain.IncludeFlags(),
-				instructionSetFlags,
+			flags.GlobalFlags = append(flags.GlobalFlags,
 				toolchain.Cflags(),
 				"${commonGlobalCflags}",
-				fmt.Sprintf("${%sGlobalCflags}", ctx.Arch().HostOrDevice),
-			}
+				fmt.Sprintf("${%sGlobalCflags}", ctx.Arch().HostOrDevice))
 		}
 
 		if ctx.Host() {