Implement EGL_ANDROID_image_native_buffer.

BUG=angleproject:2508

Change-Id: I8ef2ce8320edeb336727905055f47bb299dec2ea
Reviewed-on: https://chromium-review.googlesource.com/c/1238886
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/renderer/DisplayImpl.cpp b/src/libANGLE/renderer/DisplayImpl.cpp
index 80c044a..cbfc1a8 100644
--- a/src/libANGLE/renderer/DisplayImpl.cpp
+++ b/src/libANGLE/renderer/DisplayImpl.cpp
@@ -44,6 +44,15 @@
     return egl::EglBadDisplay() << "DisplayImpl::validateClientBuffer unimplemented.";
 }
 
+egl::Error DisplayImpl::validateImageClientBuffer(const gl::Context *context,
+                                                  EGLenum target,
+                                                  EGLClientBuffer clientBuffer,
+                                                  const egl::AttributeMap &attribs) const
+{
+    UNREACHABLE();
+    return egl::EglBadDisplay() << "DisplayImpl::validateImageClientBuffer unimplemented.";
+}
+
 const egl::Caps &DisplayImpl::getCaps() const
 {
     if (!mCapsInitialized)