ImVector: Added shrink() helper. ImFont::RenderText minor optimisation for debug build. Misc: Metrics shows tab names because we now have them.

imgui.h

@@ -1273,6 +1273,7 @@ struct ImVector
     inline int          _grow_capacity(int sz) const        { int new_capacity = Capacity ? (Capacity + Capacity/2) : 8; return new_capacity > sz ? new_capacity : sz; }
     inline void         resize(int new_size)                { if (new_size > Capacity) reserve(_grow_capacity(new_size)); Size = new_size; }
     inline void         resize(int new_size, const T& v)    { if (new_size > Capacity) reserve(_grow_capacity(new_size)); if (new_size > Size) for (int n = Size; n < new_size; n++) memcpy(&Data[n], &v, sizeof(v)); Size = new_size; }
+    inline void         shrink(int new_size)                { IM_ASSERT(new_size <= Size); Size = new_size; }
     inline void         reserve(int new_capacity)           { if (new_capacity <= Capacity) return; T* new_data = (T*)IM_ALLOC((size_t)new_capacity * sizeof(T)); if (Data) { memcpy(new_data, Data, (size_t)Size * sizeof(T)); IM_FREE(Data); } Data = new_data; Capacity = new_capacity; }
 
     // NB: It is illegal to call push_back/push_front/insert with a reference pointing inside the ImVector data itself! e.g. v.push_back(v[10]) is forbidden.