Fix #134152: Grease Pencil: Keyframe color missing in viewport text overlays

Use `TH_TIME_GP_KEYFRAME` theme to color the object name in viewport
when there are any keyframes on any layer.

Pull Request: https://projects.blender.org/blender/blender/pulls/134161

source/blender/editors/space_view3d/view3d_draw.cc

@@ -24,6 +24,7 @@
 #include "BKE_context.hh"
 #include "BKE_customdata.hh"
 #include "BKE_global.hh"
+#include "BKE_grease_pencil.hh"
 #include "BKE_image.hh"
 #include "BKE_key.hh"
 #include "BKE_layer.hh"
@@ -1322,6 +1323,22 @@ static void draw_viewport_name(ARegion *region, View3D *v3d, int xoffset, int *y
   BLF_draw_default(xoffset, *yoffset, 0.0f, name, sizeof(tmpstr));
 }
 
+static bool is_grease_pencil_with_layer_keyframe(const Object &ob)
+{
+  if (ob.type != OB_GREASE_PENCIL) {
+    return false;
+  }
+
+  using namespace blender::bke::greasepencil;
+  const GreasePencil &grease_pencil = *static_cast<GreasePencil *>(ob.data);
+  for (const Layer *layer : grease_pencil.layers()) {
+    if (!layer->frames().is_empty()) {
+      return true;
+    }
+  }
+  return false;
+}
+
 /**
  * Draw info beside axes in top-left corner:
  * frame-number, collection, object name, bone name (if available), marker name (if available).
@@ -1424,6 +1441,10 @@ static void draw_selected_name(
     }
 
     /* color depends on whether there is a keyframe */
+    if (is_grease_pencil_with_layer_keyframe(*ob)) {
+      UI_FontThemeColor(font_id, TH_TIME_GP_KEYFRAME);
+    }
+
     if (blender::animrig::id_frame_has_keyframe((ID *)ob,
                                                 /* BKE_scene_ctime_get(scene) */ float(cfra)))
     {