Tables: tooltip on clipped TableHeader() (amended)

imgui_internal.h

@@ -1429,6 +1429,7 @@ struct ImGuiContext
     float                   DragSpeedDefaultRatio;              // If speed == 0.0f, uses (max-min) * DragSpeedDefaultRatio
     float                   ScrollbarClickDeltaToGrabCenter;    // Distance between mouse and center of grab box, normalized in parent space. Use storage?
     int                     TooltipOverrideCount;
+    float                   TooltipSlowDelay;                   // Time before slow tooltips appears (FIXME: This is temporary until we merge in tooltip timer+priority work)
     ImVector<char>          ClipboardHandlerData;               // If no custom clipboard handler is defined
     ImVector<ImGuiID>       MenusIdSubmittedThisFrame;          // A list of menu IDs that were rendered at least once
 
@@ -1589,6 +1590,7 @@ struct ImGuiContext
         DragSpeedDefaultRatio = 1.0f / 100.0f;
         ScrollbarClickDeltaToGrabCenter = 0.0f;
         TooltipOverrideCount = 0;
+        TooltipSlowDelay = 0.50f;
 
         PlatformImePos = PlatformImeLastPos = ImVec2(FLT_MAX, FLT_MAX);
         PlatformLocaleDecimalPoint = '.';