Generate INVALID_OPERATION when the copy texture destination level is missing.

TEST=conformance2/textures/misc/tex-image-with-bad-args-from-dom-elements

BUG=angleproject:1932

Change-Id: I6e0e9213d86a72aa092131189ecaefa60afa4194
Reviewed-on: https://chromium-review.googlesource.com/538864
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/validationES2.cpp b/src/libANGLE/validationES2.cpp
index 08fbc50..9c70860 100644
--- a/src/libANGLE/validationES2.cpp
+++ b/src/libANGLE/validationES2.cpp
@@ -3742,8 +3742,9 @@
 
     if (dest->getWidth(destTarget, destLevel) == 0 || dest->getHeight(destTarget, destLevel) == 0)
     {
-        context->handleError(
-            InvalidValue() << "The destination level of the destination texture must be defined.");
+        context
+            ->handleError(InvalidOperation()
+                          << "The destination level of the destination texture must be defined.");
         return false;
     }