Remove deprecated WITH_HOST_DALVIK.

Bug: 13751317
Fix the Mac build:
 - disable x86 selector removal that causes OS/X 10.9 kernel panics,
 - madvise don't need does zero memory on the Mac, factor into MemMap
   routine,
 - switch to the elf.h in elfutils to avoid Linux kernel dependencies,
 - we can't rely on exclusive_owner_ being available from other pthread
   libraries so maintain our own when futexes aren't available (we
   can't rely on the OS/X 10.8 hack any more),
 - fix symbol naming in assembly code,
 - work around C library differences,
 - disable backtrace in DumpNativeStack to avoid a broken libbacktrace
   dependency,
 - disable main thread signal handling logic,
 - align the stack in stub_test,
 - use $(HOST_SHLIB_SUFFIX) rather than .so in host make file variables.

Not all host tests are passing on the Mac with this change. dex2oat
works as does running HelloWorld.
Change-Id: I5a232aedfb2028524d49daa6397a8e60f3ee40d3
diff --git a/runtime/base/unix_file/mapped_file.h b/runtime/base/unix_file/mapped_file.h
index 28cc551..73056e9 100644
--- a/runtime/base/unix_file/mapped_file.h
+++ b/runtime/base/unix_file/mapped_file.h
@@ -32,8 +32,13 @@
  public:
   // File modes used in Open().
   enum FileMode {
+#ifdef __linux__
     kReadOnlyMode = O_RDONLY | O_LARGEFILE,
     kReadWriteMode = O_CREAT | O_RDWR | O_LARGEFILE,
+#else
+    kReadOnlyMode = O_RDONLY,
+    kReadWriteMode = O_CREAT | O_RDWR,
+#endif
   };
 
   MappedFile() : FdFile(), file_size_(-1), mapped_file_(NULL) {