Tweak PathProviderPosix's FILE_EXE and FILE_MODULE handling on FreeBSD.

base/base_paths_linux.cc

Index: base/base_paths_linux.cc
diff --git a/base/base_paths_linux.cc b/base/base_paths_linux.cc
index b082eb3b3d71e6811ed385541df2df7268d1bb0e..d1b56430f2ea42211bbb2bb7eb9700858c109de4 100644
--- a/base/base_paths_linux.cc
+++ b/base/base_paths_linux.cc
@@ -50,13 +50,14 @@ bool PathProviderPosix(int key, FilePath* result) {
       int name[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
       char bin_dir[PATH_MAX + 1];
       size_t length = sizeof(bin_dir);
+      // Upon return, |length| is the number of bytes written to |bin_dir|
+      // including the string terminator.
       int error = sysctl(name, 4, bin_dir, &length, NULL, 0);
-      if (error < 0 || length == 0 || strlen(bin_dir) == 0) {
+      if (error < 0 || length <= 1) {
         NOTREACHED() << "Unable to resolve path.";
         return false;
       }
-      bin_dir[strlen(bin_dir)] = 0;
-      *result = FilePath(bin_dir);
+      *result = FilePath(FilePath::StringType(bin_dir, length - 1));
       return true;
 #elif defined(OS_SOLARIS)
       char bin_dir[PATH_MAX + 1];