LIVE: Code projects using TextureRenderTarget2D will not build because UTextureRenderTarget is undefined in TextureRenderTarget2D

If a TextureRenderTarget2D is used in a code class, the build of the project will fail with an error stating that the UTextureRenderTarget base class is undefined. The line #include "Engine/TextureRenderTarget.h" needs to be added to TextureRenderTarget2D.h in order to build the project.

1. Create a new project using the First Person Code template.
2. Build the project in Visual Studio.
3. Open the project in the Editor.
4. Add a new code class to the project derived from AHUD.
5. In the header file add the following include: #include "Engine/TextureRenderTarget2D.h"
6. In the class section of the header file, add the following lines:

   	virtual void DrawHUD() override;
   	
   	UTextureRenderTarget2D* MiniMapTex;
   

7. In the .cpp file add the following code:

   #include "CanvasItem.h"
   
   void AMyHUD::DrawHUD()
   {
   	Super::DrawHUD();
   
   	FVector2D MiniMapDrawPosition(0, 0);
   
   	FCanvasTileItem MiniMapTileItem(MiniMapDrawPosition, MiniMapTex->Resource, FLinearColor::White);
   }
   

8. Build the project in Visual Studio.

RESULTS:
The build fails with the following error:

1>D:\Main-Builds\UE4\Engine\Source\Runtime\Engine\Classes\Engine/TextureRenderTarget2D.h(17): error C2504: 'UTextureRenderTarget' : base class undefined

EXPECTED:
The build completes successfully.

UE 4.5.1: Code project featuring UTextureRenderTarget2D reference won't compile despite #include "Engine/TextureRenderTarget2D.h" in .cpp file