Refactor dump_memory function.

- Add dumping memory around registers for x86/x86_64.
- Add unit tests for new dump_memory function.
- Cleanup all of the machine.cpp files.
- Increase the high address check for 32 bit, and decrease the high
  address allowed for 64 bit slightly to match mips64.

Bug: 21206576
(cherry picked from commit e8bc77eb845ab5557a4c98fe0da604d4a3740bef)

Change-Id: I49ec237e30076a232f084da1072bf9aba15dc0cd
diff --git a/debuggerd/utility.h b/debuggerd/utility.h
index 49b46e8..263374d 100644
--- a/debuggerd/utility.h
+++ b/debuggerd/utility.h
@@ -21,6 +21,8 @@
 #include <stdbool.h>
 #include <sys/types.h>
 
+#include <backtrace/Backtrace.h>
+
 // Figure out the abi based on defined macros.
 #if defined(__arm__)
 #define ABI_STRING "arm"
@@ -75,6 +77,6 @@
 
 int wait_for_sigstop(pid_t, int*, bool*);
 
-void dump_memory(log_t* log, pid_t tid, uintptr_t addr);
+void dump_memory(log_t* log, Backtrace* backtrace, uintptr_t addr, const char* fmt, ...);
 
 #endif // _DEBUGGERD_UTILITY_H