Implement state tracking for BASE/MAX_LEVEL, and MIN/MAX_LOD.

BUG=angle:596

Change-Id: I773720a19b766c7a6930967983db0a34e84f2790
Reviewed-on: https://chromium-review.googlesource.com/193235
Tested-by: Nicolas Capens <nicolascapens@chromium.org>
Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libGLESv2/validationES.cpp b/src/libGLESv2/validationES.cpp
index 9001561..da92729 100644
--- a/src/libGLESv2/validationES.cpp
+++ b/src/libGLESv2/validationES.cpp
@@ -790,7 +790,10 @@
 
       case GL_TEXTURE_BASE_LEVEL:
       case GL_TEXTURE_MAX_LEVEL:
-        UNIMPLEMENTED();
+        if (param < 0)
+        {
+            return gl::error(GL_INVALID_VALUE, false);
+        }
         return true;
 
       default: