Removed IMGUI_API from inline templated classes. (#4962)

imgui_internal.h

@@ -541,7 +541,7 @@ inline void     ImBitArraySetBitRange(ImU32* arr, int n, int n2) // Works on ran
 // Helper: ImBitArray class (wrapper over ImBitArray functions)
 // Store 1-bit per value.
 template<int BITCOUNT, int OFFSET = 0>
-struct IMGUI_API ImBitArray
+struct ImBitArray
 {
     ImU32           Storage[(BITCOUNT + 31) >> 5];
     ImBitArray()                                { ClearAllBits(); }
@@ -622,7 +622,7 @@ struct ImSpanAllocator
 // Honor constructor/destructor. Add/remove invalidate all pointers. Indexes have the same lifetime as the associated object.
 typedef int ImPoolIdx;
 template<typename T>
-struct IMGUI_API ImPool
+struct ImPool
 {
     ImVector<T>     Buf;        // Contiguous data
     ImGuiStorage    Map;        // ID->Index
@@ -659,7 +659,7 @@ struct IMGUI_API ImPool
 // We store the chunk size first, and align the final size on 4 bytes boundaries.
 // The tedious/zealous amount of casting is to avoid -Wcast-align warnings.
 template<typename T>
-struct IMGUI_API ImChunkStream
+struct ImChunkStream
 {
     ImVector<char>  Buf;