Use task_t, thread_t, and exception_handler_t uniformly

util/mach/mach_extensions.cc

Index: util/mach/mach_extensions.cc
diff --git a/util/mach/mach_extensions.cc b/util/mach/mach_extensions.cc
index d012538e694cd2f999eb89b3e31e642bb101650b..86ca7bf24b6cb19a80f5461e0d6a011f5324b8e9 100644
--- a/util/mach/mach_extensions.cc
+++ b/util/mach/mach_extensions.cc
@@ -21,8 +21,8 @@
 
 namespace crashpad {
 
-mach_port_t MachThreadSelf() {
-  // The pthreads library keeps its own copy of the mach_port_t. Using it does
+thread_t MachThreadSelf() {
+  // The pthreads library keeps its own copy of the thread port. Using it does
   // not increment its reference count.
   return pthread_mach_thread_np(pthread_self());
 }