Fix typo in file_system_access_permission_grant.h

PermssionContext -> PermissionContext

Bug: N/A
Change-Id: I2934e259a7c5640998ed702e2ac2d09e660958a3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2618520
Auto-Submit: Austin Sullivan <asully@chromium.org>
Commit-Queue: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843391}

content/public/browser/file_system_access_permission_grant.h

@@ -25,7 +25,7 @@ namespace content {
 // FileSystemAccessPermissionContext instance.
 //
 // FileSystemAccessPermissionGrant instances are not thread safe, and should
-// only be used (and referenced) on the same sequence as the PermssionContext
+// only be used (and referenced) on the same sequence as the PermissionContext
 // that created them, i.e. the UI thread.
 class CONTENT_EXPORT FileSystemAccessPermissionGrant
     : public base::RefCounted<FileSystemAccessPermissionGrant> {