HeadphoneKey(runAction): Take `strlen` out of loop

This appears to fix the weirdness I was having in
815bf3e8601b6d0cfb0296c6f2c302aaf5059b23, where extra characters were
getting sent to `simpleKeyPressWithKey:` even though there was only 1
element (the correct number of elements) in the `action` array/string.

I guess before the length was getting recalculated on each iteration of
the loop.

Previously, this would result in the Vim `x` command getting entered
just after the map action (for example `j`).

Now it appears to work correctly.

1 files changed, 2 insertions, 1 deletions

diff --git a/DomeKey/HeadphoneKey.m b/DomeKey/HeadphoneKey.m
index e955128..1d5811b 100644
--- a/DomeKey/HeadphoneKey.m
+++ b/DomeKey/HeadphoneKey.m
@@ -77,7 +77,8 @@
     const CKeyActionResult *result = c_run_key_action(trigger, count);
 
     if (*result->kind == MapKind_Map) {
-        for (int i = 0; i < strlen(result->action); i++) {
+        size_t length = strlen(result->action);
+        for (size_t i = 0; i < length; i++) {
             [KeyboardSimulator simpleKeyPressWithKey:result->action[i]];
         }
     }