Adds Objective C++ Build capabilities to cscore mac (#1029)

cscore/build.gradle

@@ -5,6 +5,10 @@ ext {
     devMain = 'edu.wpi.cscore.DevMain'
 }
 
+if (OperatingSystem.current().isMacOsX()) {
+    apply plugin: 'objective-cpp'
+}
+
 apply from: "${rootDir}/shared/jni/setupBuild.gradle"
 
 ext {
@@ -15,6 +19,21 @@ ext {
     staticCvConfigs = [cscoreJNI: []]
     useJava = true
     useCpp = true
+    splitSetup = {
+        if (it.targetPlatform.operatingSystem.name == 'osx') {
+            it.sources {
+                macObjCpp(ObjectiveCppSourceSet) {
+                    source {
+                        srcDirs = ['src/main/native/objcpp']
+                        include '**/*.mm'
+                    }
+                    exportedHeaders {
+                        srcDirs 'src/main/native/include'
+                    }
+                }
+            }
+        }
+    }
 }
 
 def examplesMap = [:];

cscore/src/main/native/objcpp/objcpptemp.mm

@@ -0,0 +1,12 @@
+#import <Foundation/Foundation.h>
+
+@interface XYZPerson : NSObject
+- (void)sayHello;
+@end
+
+
+@implementation XYZPerson
+- (void)sayHello {
+    NSLog(@"Hello, World!");
+}
+@end

shared/config.gradle

@@ -21,8 +21,10 @@ def macCompilerArgs = ['-std=c++14', '-Wall', '-Wextra', '-Werror', '-pedantic-e
                        '-Wno-unused-const-variable', '-pthread']
 def macCCompilerArgs = ['-Wall', '-Wextra', '-Werror', '-pedantic-errors', '-fPIC', '-g',
                         '-Wno-unused-parameter', '-Wno-missing-field-initializers', '-Wno-unused-private-field']
+def macObjCLinkerArgs = ['-std=c++14', '-stdlib=libc++','-fobjc-arc', '-g', '-fPIC', '-Wall', '-Wextra', '-Werror']
 def macReleaseCompilerArgs = ['-O2']
 def macDebugCompilerArgs = ['-O0']
+def macLinkerArgs = ['-framework', 'CoreFoundation', '-framework', 'AVFoundation', '-framework', 'Foundation', '-framework', 'CoreMedia', '-framework', 'CoreVideo']
 def mac32BitArg = '-m32'
 
 def buildAll = project.hasProperty('buildAll')
@@ -158,6 +160,8 @@ if (!project.hasProperty('onlyAthena')) {
                 CCompilerArgs = macCCompilerArgs
                 debugCompilerArgs = macDebugCompilerArgs
                 releaseCompilerArgs = macReleaseCompilerArgs
+                objCppCompilerArgs = macObjCLinkerArgs
+                linkerArgs = macLinkerArgs
                 releaseStripBinaries = true
                 compilerFamily = 'Clang'
                 detectPlatform = mac64PlatformDetect