Refine PNaCl pexe fetch UMA errors to know if the user aborted, etc.

ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc

 // Copyright (c) 2012 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 "native_client/src/trusted/plugin/pnacl_translate_thread.h"
 
 #include "native_client/src/trusted/desc/nacl_desc_wrapper.h"
 #include "native_client/src/trusted/plugin/plugin.h"
 #include "native_client/src/trusted/plugin/plugin_error.h"
 #include "native_client/src/trusted/plugin/pnacl_resources.h"
@@ skipping 182 matching lines @@
     }
   }
   PLUGIN_PRINTF(("PnaclTranslateThread done with chunks\n"));
   // Finish llc.
   if(!llc_subprocess_->InvokeSrpcMethod("StreamEnd",
                                        "",
                                        &params)) {
     PLUGIN_PRINTF(("PnaclTranslateThread StreamEnd failed\n"));
     if (llc_subprocess_->srpc_client()->GetLastError() ==
         NACL_SRPC_RESULT_APP_ERROR) {
-      // The error string is only present if the error was sent back from llc
+      // The error string is only present if the error was sent back from llc.
       TranslateFailed(ERROR_PNACL_LLC_INTERNAL,
                       params.outs()[3]->arrays.str);
     } else {
       TranslateFailed(ERROR_PNACL_LLC_INTERNAL,
                       "Compile StreamEnd internal error");
     }
     return;
   }
   // LLC returns values that are used to determine how linking is done.
   int is_shared_library = (params.outs()[0]->u.ival != 0);
@@ skipping 110 matching lines @@
   PLUGIN_PRINTF(("~PnaclTranslateThread (translate_thread=%p)\n", this));
   AbortSubprocesses();
   NaClThreadJoin(translate_thread_.get());
   PLUGIN_PRINTF(("~PnaclTranslateThread joined\n"));
   NaClCondVarDtor(&buffer_cond_);
   NaClMutexDtor(&cond_mu_);
   NaClMutexDtor(&subprocess_mu_);
 }
 
 } // namespace plugin