Implemented mid-level Negotiate protocol for Posix.

base/native_library_linux.cc

Index: base/native_library_linux.cc
diff --git a/base/native_library_linux.cc b/base/native_library_linux.cc
index 99e32c6229ecd6c71f1ef840662a403586a3e329..f31c799b6459f6e9cc2e405e2b0f538c26e7cc95 100644
--- a/base/native_library_linux.cc
+++ b/base/native_library_linux.cc
@@ -45,7 +45,9 @@ void UnloadNativeLibrary(NativeLibrary library) {
 // static
 void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
                                           const char* name) {
-  return dlsym(library, name);
+  DCHECK(name != NULL) << "NULL name passed in.";
+  void* lib = dlsym(library, name);
+  return lib;
 }
 
 // static
@@ -53,4 +55,15 @@ string16 GetNativeLibraryName(const string16& name) {
   return ASCIIToUTF16("lib") + name + ASCIIToUTF16(".so");
 }
 
+string16 GetLibraryErrorMessage() {
+  const char* last_err_message = dlerror();
+  string16 err_message;
+
+  if (last_err_message) {
+    err_message = ASCIIToUTF16(last_err_message);
+  }
+
+  return err_message;
+}
+
 }  // namespace base