Use dlerror() for in generated stub loading code for more informative…

… error messages.

Review URL: http://codereview.chromium.org/7811025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@99079 0039d316-1c4b-4281-b951-d872f2087c98

tools/generate_stubs/generate_stubs.py

@@ -233,7 +233,8 @@ def __str__(self):
 STUB_POINTER_INITIALIZER = """  %(name)s_ptr =
     reinterpret_cast<%(return_type)s (*)(%(parameters)s)>(
       dlsym(module, "%(name)s"));
-    VLOG_IF(1, !%(name)s_ptr) << "Couldn't load %(name)s";
+    VLOG_IF(1, !%(name)s_ptr) << "Couldn't load %(name)s, dlerror() says:\\n"
+        << dlerror();
 """
 
 # Template for module initializer function start and end.  This template takes
@@ -299,7 +300,8 @@ def __str__(self):
         module_opened = true;
         opened_libraries[cur_module] = handle;
       } else {
-        VLOG(1) << "dlopen(" << dso_path->c_str() << ") failed";
+        VLOG(1) << "dlopen(" << dso_path->c_str() << ") failed, "
+                << "dlerror() says:\\n" << dlerror();
       }
     }