message: BeginTooltipEx() internal tweaks
diff: @@ -3412,7 +3412,7 @@ static ImRect GetVisibleRect()
  }
  // Not exposed publicly as BeginTooltip() because bool parameters are evil. Let's see if other needs arise first.
  -static void BeginTooltipEx(bool override_previous_tooltip)
  +static void BeginTooltipEx(ImGuiWindowFlags extra_flags, bool override_previous_tooltip)
  {
  ImGuiContext& g = *GImGui;
  char window_name[16];
  @@ -3425,12 +3425,13 @@ static void BeginTooltipEx(bool override_previous_tooltip)
  window->HiddenFrames = 1;
  ImFormatString(window_name, IM_ARRAYSIZE(window_name), "##Tooltip%02d", ++g.TooltipOverrideCount);
  }
  - ImGui::Begin(window_name, NULL, ImGuiWindowFlags_Tooltip|ImGuiWindowFlags_NoTitleBar|ImGuiWindowFlags_NoMove|ImGuiWindowFlags_NoResize|ImGuiWindowFlags_NoSavedSettings|ImGuiWindowFlags_AlwaysAutoResize);
  + ImGuiWindowFlags flags = ImGuiWindowFlags_Tooltip|ImGuiWindowFlags_NoTitleBar|ImGuiWindowFlags_NoMove|ImGuiWindowFlags_NoResize|ImGuiWindowFlags_NoSavedSettings|ImGuiWindowFlags_AlwaysAutoResize;
  + ImGui::Begin(window_name, NULL, flags | extra_flags);
  }
  void ImGui::SetTooltipV(const char* fmt, va_list args)
  {
  - BeginTooltipEx(true);
  + BeginTooltipEx(0, true);
  TextV(fmt, args);
  EndTooltip();
  }
  @@ -3445,7 +3446,7 @@ void ImGui::SetTooltip(const char* fmt, ...)
  void ImGui::BeginTooltip()
  {
  - BeginTooltipEx(false);
  + BeginTooltipEx(0, false);
  }
  void ImGui::EndTooltip()
  @@ -9136,7 +9137,7 @@ void ImGui::ColorTooltip(const char* text, const float col[4], ImGuiColorEditFla
  ImGuiContext& g = *GImGui;
  int cr = IM_F32_TO_INT8_SAT(col[0]), cg = IM_F32_TO_INT8_SAT(col[1]), cb = IM_F32_TO_INT8_SAT(col[2]), ca = (flags & ImGuiColorEditFlags_NoAlpha) ? 255 : IM_F32_TO_INT8_SAT(col[3]);
  - BeginTooltipEx(true);
  + BeginTooltipEx(0, true);
  const char* text_end = text ? FindRenderedTextEnd(text, NULL) : text;
  if (text_end > text)
  