Android: Introduce ANDROID_HOST_BUILD and rework logging.

Avoid using the Android logger directly. Instead, use the Common/Debug
and OpenGL/common/debug paths instead, which abstracts away use of the
logger.

Add ANDRIOD_HOST_BUILD to tell the build we are building an Android
swiftshader, but minimizing the use of platform features such as the
logger.

Change-Id: Ic6c70843d947c568d0e29fe66c55af74b8559a59
Reviewed-on: https://swiftshader-review.googlesource.com/18028
Tested-by: Alistair Strachan <astrachan@google.com>
Reviewed-by: Greg Hartman <ghartman@google.com>
Reviewed-by: Lingfeng Yang <lfy@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
diff --git a/src/OpenGL/compiler/debug.h b/src/OpenGL/compiler/debug.h
index 2755d23..77798ef 100644
--- a/src/OpenGL/compiler/debug.h
+++ b/src/OpenGL/compiler/debug.h
@@ -17,7 +17,7 @@
 #ifndef COMPILER_DEBUG_H_
 #define COMPILER_DEBUG_H_
 
-#ifdef __ANDROID__
+#if defined(__ANDROID__) && !defined(ANDROID_HOST_BUILD)
 #include "../../Common/DebugAndroid.hpp"
 
 #define Trace(...) ((void)0)