Adding UIKit as a dependence for CoreGraphics UnitTests, this is due …

…to CGColor is an instance of UIColor (which is lazy loaded).

Thus for CGColorTests to run we need the UIKit DLL to be loaded.
Note: The CGColorTests are appended with [UIColor class] to support the UIKit dll to be part of the test run.

build/Tests/UnitTests/CoreGraphics/CoreGraphics.UnitTests.vcxproj

@@ -40,6 +40,9 @@
     <ProjectReference Include="..\..\..\CoreImage\dll\CoreImage.vcxproj">
       <Project>{3EFCDFF3-6013-448F-8611-534D0F819D6B}</Project>
     </ProjectReference>
+    <ProjectReference Include="..\..\..\UIKit\dll\UIKit.vcxproj">
+      <Project>{43D2CFE5-0711-4E61-8F5C-F8D3B65D3A49}</Project>
+    </ProjectReference>
   </ItemGroup>
   <PropertyGroup Label="Globals">
     <ProjectGuid>{DA6C01EA-A22E-4807-BACE-63C5C6ABAE77}</ProjectGuid>

tests/unittests/CoreGraphics/CGColorTests.mm

@@ -17,13 +17,21 @@
 #import <TestFramework.h>
 #import <CoreGraphics/CoreGraphics.h>
 
+// TODO #2243: Remove the UIKit dependency
+#if WINOBJC
+#include <UIKit/UIColor.h>
+#endif
+
 #define EXPECT_EQ_COMPONENTS(a, b) \
     EXPECT_EQ((a)[0], (b)[0]);     \
     EXPECT_EQ((a)[1], (b)[1]);     \
     EXPECT_EQ((a)[2], (b)[2]);     \
     EXPECT_EQ((a)[3], (b)[3])
 
 TEST(CGColor, CGColorGetComponents) {
+#if WINOBJC
+    [UIColor class];
+#endif
     CGFloat colors[] = { 1, 0, 0, 1 }; // bright red
 
     CGColorSpaceRef clrRgb = CGColorSpaceCreateDeviceRGB();
@@ -49,6 +57,10 @@
 }
 
 TEST(CGColor, CGColorEquals) {
+#if WINOBJC
+    [UIColor class];
+#endif
+
     CGFloat colors[] = { 1, 0, 0, 1 }; // bright red
 
     CGColorSpaceRef clrRgb = CGColorSpaceCreateDeviceRGB();
@@ -80,6 +92,9 @@
 }
 
 TEST(CGColor, GetColorSpace) {
+#if WINOBJC
+    [UIColor class];
+#endif
     CGFloat colors[] = { 1, 0, 0, 1 }; // bright red
 
     CGColorSpaceRef clrRgb = CGColorSpaceCreateDeviceRGB();
@@ -101,6 +116,9 @@
 }
 
 TEST(CGColor, GetConstantColor) {
+#if WINOBJC
+    [UIColor class];
+#endif
     auto grayColorSpace = woc::MakeStrongCF<CGColorSpaceRef>(CGColorSpaceCreateDeviceGray());
 
     CFStringRef colors[] = { kCGColorWhite, kCGColorBlack, kCGColorClear };