Switch over to the google3 unix_file File*.

I also moved macros.h to base/macros.h to ease google3 porting, at
the expense of a larger than necessary change. (I learned my lesson,
though, and didn't make the equivalent base/logging.h change.)

I'm not sure whether we want to keep the unix_file MappedFile given
our existing MemMap, but it's easier to bring it over and then remove
it (and possibly revert the removal) than to bring it over later.

Change-Id: Id50a66faa5ab17b9bc936cc9043dbc26f791f0ca
diff --git a/src/image_test.cc b/src/image_test.cc
index feb490c..a250b13 100644
--- a/src/image_test.cc
+++ b/src/image_test.cc
@@ -18,7 +18,6 @@
 #include <vector>
 
 #include "common_test.h"
-#include "file.h"
 #include "image.h"
 #include "image_writer.h"
 #include "oat_writer.h"
@@ -71,7 +70,7 @@
     ASSERT_FALSE(space->IsImageSpace());
     ASSERT_TRUE(space != NULL);
     ASSERT_TRUE(space->IsAllocSpace());
-    ASSERT_GE(sizeof(image_header) + space->Size(), static_cast<size_t>(file->Length()));
+    ASSERT_GE(sizeof(image_header) + space->Size(), static_cast<size_t>(file->GetLength()));
   }
 
   // Need to delete the compiler since it has worker threads which are attached to runtime.