Bug 1586674 - Simplify 'static inline uint32_t PRTimeToSeconds(PRTime aTimeUsec)' r=valentin

Differential Revision: https://phabricator.services.mozilla.com/D48303

--HG--
extra : moz-landing-system : lando

docshell/base/nsDocShell.h

@@ -522,8 +522,7 @@ class nsDocShell final : public nsDocLoader,
                              nsIDocShellTreeItem* aTargetTreeItem);
 
   static inline uint32_t PRTimeToSeconds(PRTime aTimeUsec) {
-    PRTime usecPerSec = PR_USEC_PER_SEC;
-    return uint32_t(aTimeUsec /= usecPerSec);
+    return uint32_t(aTimeUsec / PR_USEC_PER_SEC);
   }
 
   static const nsCString FrameTypeToString(uint32_t aFrameType) {