Code layout cleanup

- Fwd declare where possible
- List .h first in the .cpp to verify proper includes
- Remove hacky -internal.h file and move testBitInRange to a new component

Change-Id: I442248c4b32738c6c2af250f45d4c8822c862e08
diff --git a/modules/input/evdev/InputMapper.cpp b/modules/input/evdev/InputMapper.cpp
index 2353a9a..3893125 100644
--- a/modules/input/evdev/InputMapper.cpp
+++ b/modules/input/evdev/InputMapper.cpp
@@ -16,6 +16,8 @@
 
 #include "InputMapper.h"
 
+#include "InputHost.h"
+
 namespace android {
 
 InputReport* InputMapper::getInputReport() {