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

ppapi/native_client/src/trusted/plugin/plugin_error.h

Index: ppapi/native_client/src/trusted/plugin/plugin_error.h
diff --git a/ppapi/native_client/src/trusted/plugin/plugin_error.h b/ppapi/native_client/src/trusted/plugin/plugin_error.h
index 1654846f85b77c4c2cb8c6206dc77903d4db95f6..00c8b75c9d96d406a7366b6fc6ba52e0606da25a 100644
--- a/ppapi/native_client/src/trusted/plugin/plugin_error.h
+++ b/ppapi/native_client/src/trusted/plugin/plugin_error.h
@@ -84,16 +84,18 @@ enum PluginErrorCode {
   ERROR_PNACL_CACHE_FINALIZE_RENAME_NOACCESS = 56,
   ERROR_PNACL_CACHE_FINALIZE_RENAME_OTHER = 57,
   ERROR_PNACL_RESOURCE_FETCH = 58,
-  ERROR_PNACL_PEXE_FETCH = 59,
-  ERROR_PNACL_THREAD_CREATE = 60,
-  ERROR_PNACL_LLC_SETUP = 61,
-  ERROR_PNACL_LD_SETUP = 62,
-  ERROR_PNACL_LLC_INTERNAL = 63,
-  ERROR_PNACL_LD_INTERNAL = 64,
-  ERROR_PNACL_CREATE_TEMP = 65,
+  ERROR_PNACL_PEXE_FETCH_ABORTED = 59,
+  ERROR_PNACL_PEXE_FETCH_NOACCESS = 60,
+  ERROR_PNACL_PEXE_FETCH_OTHER = 61,
+  ERROR_PNACL_THREAD_CREATE = 62,
+  ERROR_PNACL_LLC_SETUP = 63,
+  ERROR_PNACL_LD_SETUP = 64,
+  ERROR_PNACL_LLC_INTERNAL = 65,
+  ERROR_PNACL_LD_INTERNAL = 66,
+  ERROR_PNACL_CREATE_TEMP = 67,
   // Remove this next code when pnacl is no longer behind a flag (when we
   // remove the --enable-pnacl flag).
-  ERROR_PNACL_NOT_ENABLED = 66,
+  ERROR_PNACL_NOT_ENABLED = 68,
   // If you add a code, read the enum comment above on how to update histograms.
   ERROR_MAX
 };