Tell editors that these are Makefiles (or fragments thereof).

Change-Id: I0c5e29ac750b9605b1e8f823d6998d31a933b7a4
diff --git a/Android.mk b/Android.mk
index 421e01d..14b1e32 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 # Copyright (C) 2009 The Android Open Source Project
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
diff --git a/CleanSpec.mk b/CleanSpec.mk
index 2207d3e..1618f1b 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 # Copyright (C) 2007 The Android Open Source Project
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
diff --git a/Docs.mk b/Docs.mk
index 13eddec..1f75a5e 100644
--- a/Docs.mk
+++ b/Docs.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 # List of libcore directories to include in documentation.
 # Shared between libcore and frameworks/base.
 
diff --git a/NativeCode.mk b/NativeCode.mk
index b5cc769..d4960c5 100644
--- a/NativeCode.mk
+++ b/NativeCode.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 # Copyright (C) 2007 The Android Open Source Project
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -101,7 +102,7 @@
 LOCAL_MODULE := libjavacore
 
 ifneq ($(TARGET_SIMULATOR),true)
-LOCAL_C_INCLUDES += external/stlport/stlport bionic/ bionic/libstdc++/include 
+LOCAL_C_INCLUDES += external/stlport/stlport bionic/ bionic/libstdc++/include
 LOCAL_SHARED_LIBRARIES += libstlport
 endif
 
diff --git a/dalvik/src/main/native/sub.mk b/dalvik/src/main/native/sub.mk
index 27d4c9c..ad62649 100644
--- a/dalvik/src/main/native/sub.mk
+++ b/dalvik/src/main/native/sub.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 # This file is included by the top-level libcore Android.mk.
 # It's not a normal makefile, so we don't include CLEAR_VARS
 # or BUILD_*_LIBRARY.
diff --git a/luni/src/main/native/sub.mk b/luni/src/main/native/sub.mk
index 1122ad7..85f3a4c 100644
--- a/luni/src/main/native/sub.mk
+++ b/luni/src/main/native/sub.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 # This file is included by the top-level libcore Android.mk.
 # It's not a normal makefile, so we don't include CLEAR_VARS
 # or BUILD_*_LIBRARY.
diff --git a/sqlite-jdbc/Android.mk b/sqlite-jdbc/Android.mk
index 8cc23ce..1e25524 100644
--- a/sqlite-jdbc/Android.mk
+++ b/sqlite-jdbc/Android.mk
@@ -1,3 +1,4 @@
+# -*- mode: makefile -*-
 
 sqlite_jdbc_src_files := \
     src/main/native/sqlite_jni.c