Add base::ExecutableExistsInPath

base/files/file_util.h

Index: base/files/file_util.h
diff --git a/base/files/file_util.h b/base/files/file_util.h
index 8fd9fffeb36d044c6e169fc24f33ccdea0dec732..83373fc8f97b24f1e348df2981ffabff52ae9dfb 100644
--- a/base/files/file_util.h
+++ b/base/files/file_util.h
@@ -199,6 +199,10 @@ BASE_EXPORT bool GetPosixFilePermissions(const FilePath& path, int* mode);
 // the permission of a file which the symlink points to.
 BASE_EXPORT bool SetPosixFilePermissions(const FilePath& path, int mode);
 
+// Returns true iff |executable| can be found in any directory specified by the
+// $PATH environment variable.
+BASE_EXPORT bool ExecutableExistsInPath(const FilePath::StringType& executable);
+
 #endif  // OS_POSIX
 
 // Returns true if the given directory is empty