Revert of Adding more logging to see why...

Revert of Adding more logging to see why DevToolsHttpHandlerImpl::BrowserTarget is flaky. (patchset #2 id:20001 of https://codereview.chromium.org/702503002/)

Reason for revert:
It was temporary and no longer needed.

Original issue's description:
> Adding more logging to see why DevToolsHttpHandlerImpl::BrowserTarget is flaky.
>
> BUG=424024
> TEST=
> TBR=kbr@chromium.org
>
> Committed: https://crrev.com/d3ac15e57aade01f1524f554e00c6113e8e9b364
> Cr-Commit-Position: refs/heads/master@{#302453}

TBR=kbr@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=424024

Review URL: https://codereview.chromium.org/702773002

Cr-Commit-Position: refs/heads/master@{#302667}

content/browser/devtools/devtools_http_handler_impl.cc

@@ -456,7 +456,6 @@ void DevToolsHttpHandlerImpl::OnHttpRequest(
 void DevToolsHttpHandlerImpl::OnWebSocketRequest(
     int connection_id,
     const net::HttpServerRequestInfo& request) {
-  VLOG(2) << "OnWebSocketRequest";
   BrowserThread::PostTask(
       BrowserThread::UI,
       FROM_HERE,
@@ -698,11 +697,8 @@ void DevToolsHttpHandlerImpl::OnDiscoveryPageRequestUI(int connection_id) {
 void DevToolsHttpHandlerImpl::OnWebSocketRequestUI(
     int connection_id,
     const net::HttpServerRequestInfo& request) {
-  VLOG(2) << "OnWebSocketRequestUI : " << request.path;
-  if (!thread_) {
-    VLOG(2) << "OnWebSocketRequestUI : !thread_";
+  if (!thread_)
     return;
-  }
 
   std::string browser_prefix = "/devtools/browser";
   size_t browser_pos = request.path.find(browser_prefix);