Fix documentation for "pool" object in gn binary.

tools/gn/functions.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "tools/gn/functions.h"
 
 #include <stddef.h>
 #include <iostream>
 #include <utility>
 
@@ skipping 674 matching lines @@
 const char kPool_HelpShort[] =
     "pool: Defines a pool object.";
 const char kPool_Help[] =
     "pool: Defines a pool object.\n"
     "\n"
     "  Pool objects can be applied to a tool to limit the parallelism of the\n"
     "  build. This object has a single property \"depth\" corresponding to\n"
     "  the number of tasks that may run simultaneously.\n"
     "\n"
     "  As the file containing the pool definition may be executed in the\n"
-    "  of more than one toolchain it is recommended to specify an explicit\n"
-    "  toolchain when definining and referencing a pool.\n"
+    "  context of more than one toolchain it is recommended to specify an\n"
+    "  explicit toolchain when defining and referencing a pool.\n"
     "\n"
     "  A pool is referenced by its label just like a target.\n"
     "\n"
     "Variables\n"
     "\n"
     "  depth*\n"
     "  * = required\n"
     "\n"
     "Example\n"
     "\n"
@@ skipping 304 matching lines @@
   }
 
   // Otherwise it's a no-block function.
   if (!VerifyNoBlockForFunctionCall(function, block, err))
     return Value();
   return found_function->second.no_block_runner(scope, function,
                                                 args.list_value(), err);
 }
 
 }  // namespace functions