wininet: Return correct errors in InternetOpenUrlW.

dlls/wininet/internet.c

@@ -2934,6 +2934,7 @@ HINTERNET WINAPI INTERNET_InternetOpenUrlW(LPWININETAPPINFOW hIC, LPCWSTR lpszUr
 	/* gopher doesn't seem to be implemented in wine, but it's supposed
 	 * to be supported by InternetOpenUrlA. */
     default:
+        INTERNET_SetLastError(ERROR_INTERNET_UNRECOGNIZED_SCHEME);
 	break;
     }
 
@@ -2963,6 +2964,12 @@ HINTERNET WINAPI InternetOpenUrlW(HINTERNET hInternet, LPCWSTR lpszUrl,
 	dump_INTERNET_FLAGS(dwFlags);
     }
 
+    if (!lpszUrl)
+    {
+        SetLastError(ERROR_INVALID_PARAMETER);
+        goto lend;
+    }
+
     hIC = (LPWININETAPPINFOW) WININET_GetObject( hInternet );
     if (NULL == hIC ||  hIC->hdr.htype != WH_HINIT) {
 	INTERNET_SetLastError(ERROR_INTERNET_INCORRECT_HANDLE_TYPE);

dlls/wininet/tests/internet.c

@@ -143,6 +143,14 @@ static void test_null(void)
   ok(GetLastError() == ERROR_INVALID_HANDLE, "wrong error\n");
   ok(hc == NULL, "connect failed\n");
 
+  hc = InternetOpenUrlW(hi, NULL, NULL, 0, 0, 0);
+  ok(GetLastError() == ERROR_INVALID_PARAMETER, "wrong error\n");
+  ok(hc == NULL, "connect failed\n");
+
+  hc = InternetOpenUrlW(hi, szServer, NULL, 0, 0, 0);
+  ok(GetLastError() == ERROR_INTERNET_UNRECOGNIZED_SCHEME, "wrong error\n");
+  ok(hc == NULL, "connect failed\n");
+
   InternetCloseHandle(hi);
 }