Convert ignore_limits from a SocketParam to a socket request argument.

net/socket/client_socket_pool.h

Index: net/socket/client_socket_pool.h
diff --git a/net/socket/client_socket_pool.h b/net/socket/client_socket_pool.h
index e1785a3a7c7bf3c9aee0f9e27b21fd57d03e1c18..7dee8c3bfc3ba584ef4c2a183bbdd9778997da96 100644
--- a/net/socket/client_socket_pool.h
+++ b/net/socket/client_socket_pool.h
@@ -61,11 +61,14 @@ class NET_EXPORT LowerLayeredPool {
 // A ClientSocketPool is used to restrict the number of sockets open at a time.
 // It also maintains a list of idle persistent sockets.
 //
+// Subclasses must also have an inner class SocketParams which is
+// the type for the |params| argument in RequestSocket() and
+// RequestSockets() below.
 class NET_EXPORT ClientSocketPool : public LowerLayeredPool {
  public:
-  // Subclasses must also have an inner class SocketParams which is
-  // the type for the |params| argument in RequestSocket() and
-  // RequestSockets() below.
+  // Indicates whether a request for a socket should ignore the SocketPool's
+  // global and per-group socket limits.
+  enum class IgnoreLimits { DISABLED, ENABLED };

[eroman, 2016/01/27 20:15:12]

Not sure what to suggest in its place, but "ENABLED" to my ear sounds like the
normal flow, and DISABLED as the exceptional case.

Ideally I would like for the name to sound scarier for the enabled case, since
this is really a very special case that callers shouldn't be using.

Maybe something that implies "default" or "normal" for the DISABLED case, or
even flipping the enum's meaning to "respect limits" or "enforce limits" so
disabled becomes the unusual case.

[mmenke, 2016/01/27 20:37:27]

Hrm...  IgnoreLimits::DEFAULT / NORMAL seems less clear to me.  Could go with
ClientSocketPool::PoolLimits::IGNORE (BYPASS?) / DEFAULT (I think we're missing
a RETRY and ABORT in there).  That does sound a bit like it affects some
permanent property of the socket pool, though, rather than a per-request value.

Think I'll just go with RespectLimits::ENABLED / DISABLED, unless you chime in. 
Now that I've stuck IgnoreLimits everywhere, mass renaming is pretty easy, just
have to be careful with comments.

[eroman, 2016/01/27 20:40:21]

ok

 
   // Requests a connected socket for a group_name.
   //
@@ -96,9 +99,12 @@ class NET_EXPORT ClientSocketPool : public LowerLayeredPool {
   // client of completion.
   //
   // Profiling information for the request is saved to |net_log| if non-NULL.
+  //
+  // If |ignore_limits| is ENABLED, priority must be HIGHEST.
   virtual int RequestSocket(const std::string& group_name,
                             const void* params,
                             RequestPriority priority,
+                            IgnoreLimits ignore_limits,
                             ClientSocketHandle* handle,
                             const CompletionCallback& callback,
                             const BoundNetLog& net_log) = 0;