[vm/mac] Hide application icon from the dock.

TEST=Passing any value other than true as an argument brings the icon to the dock.
BUG=flutter/flutter#170633

Change-Id: Ief117a0c95df3762cf1e54bc3facde8c92f7379b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/437781
Reviewed-by: Slava Egorov <[email protected]>
Commit-Queue: Alexander Aprelev <[email protected]>

Author: aam

runtime/bin/platform_macos.cc

@@ -349,7 +349,14 @@ void Platform::SetProcessName(const char* name) {
 
   _LSSetApplicationLaunchServicesServerConnectionStatus(0, nullptr);
 
-  _LSApplicationCheckIn(-2, CFBundleGetInfoDictionary(CFBundleGetMainBundle()));
+  CFMutableDictionaryRef dictionary = CFDictionaryCreateMutableCopy(
+      kCFAllocatorDefault, /*capacity=*/0,
+      CFBundleGetInfoDictionary(CFBundleGetMainBundle()));
+  if (dictionary == nullptr) return;
+  ScopedCFStringRef _kLSUIElement("LSUIElement");
+  CFDictionarySetValue(dictionary, _kLSUIElement.get(), kCFBooleanTrue);
+  _LSApplicationCheckIn(-2, dictionary);
+  CFRelease(dictionary);
 
   CFTypeRef asn;
   asn = _LSGetCurrentApplicationASN();