[cleanup] Remove explicit from 2-arg constructor

Change-Id: I42697b4692ff30c390ded25568b8d424b03bbf19
Reviewed-on: https://chromium-review.googlesource.com/c/1288450Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56764}

src/profiler/cpu-profiler.h

@@ -149,8 +149,7 @@ class ProfilerEventsProcessor : public base::Thread, public CodeEventObserver {
   void AddSample(TickSample sample);
 
  protected:
-  explicit ProfilerEventsProcessor(Isolate* isolate,
-                                   ProfileGenerator* generator);
+  ProfilerEventsProcessor(Isolate* isolate, ProfileGenerator* generator);
 
   // Called from events processing thread (Run() method.)
   bool ProcessCodeEvent();