gdiplus: Fix graphics bounds for memory DC's.

dlls/gdiplus/graphics.c

@@ -2113,6 +2113,25 @@ static GpStatus get_graphics_bounds(GpGraphics* graphics, GpRectF* rect)
         stat = GdipGetImageBounds(graphics->image, rect, &unit);
         if (stat == Ok && unit != UnitPixel)
             FIXME("need to convert from unit %i\n", unit);
+    }else if (GetObjectType(graphics->hdc) == OBJ_MEMDC){
+        HBITMAP hbmp;
+        BITMAP bmp;
+
+        rect->X = 0;
+        rect->Y = 0;
+
+        hbmp = GetCurrentObject(graphics->hdc, OBJ_BITMAP);
+        if (hbmp && GetObjectW(hbmp, sizeof(bmp), &bmp))
+        {
+            rect->Width = bmp.bmWidth;
+            rect->Height = bmp.bmHeight;
+        }
+        else
+        {
+            /* FIXME: ??? */
+            rect->Width = 1;
+            rect->Height = 1;
+        }
     }else{
         rect->X = 0;
         rect->Y = 0;

dlls/gdiplus/tests/graphics.c

@@ -4091,6 +4091,7 @@ static void test_alpha_hdc(void)
     GpGraphics *graphics;
     ULONG *bits;
     BITMAPINFO bmi;
+    GpRectF bounds;
 
     hdc = CreateCompatibleDC(0);
     ok(hdc != NULL, "CreateCompatibleDC failed\n");
@@ -4110,6 +4111,13 @@ static void test_alpha_hdc(void)
     status = GdipCreateFromHDC(hdc, &graphics);
     expect(Ok, status);
 
+    status = GdipGetVisibleClipBounds(graphics, &bounds);
+    expect(Ok, status);
+    expectf(0.0, bounds.X);
+    expectf(0.0, bounds.Y);
+    expectf(5.0, bounds.Width);
+    expectf(5.0, bounds.Height);
+
     bits[0] = 0xdeadbeef;
 
     status = GdipGraphicsClear(graphics, 0xffaaaaaa);