WinSDK: add some constants for the SDK overlay

Unfortunately, the types are not imported through the clang importer.
Add them to the overlay for use in applications.

Author: compnerd

stdlib/public/Windows/WinSDK.swift

@@ -78,6 +78,18 @@ public let UPDOWN_CLASSW: [WCHAR] = Array<WCHAR>("msctls_updown32".utf16)
 // consoleapi.h
 public let PROC_THREAD_ATTRIBUTE_PSEUDOCONSOLE: DWORD_PTR = 0x00020016
 
+// windef.h
+public let DPI_AWARENESS_CONTEXT_UNAWARE: DPI_AWARENESS_CONTEXT =
+    DPI_AWARENESS_CONTEXT(bitPattern: -1)!
+public let DPI_AWARENESS_CONTEXT_SYSTEM_AWARE: DPI_AWARENESS_CONTEXT =
+    DPI_AWARENESS_CONTEXT(bitPattern: -2)!
+public let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE: DPI_AWARENESS_CONTEXT =
+    DPI_AWARENESS_CONTEXT(bitPattern: -3)!
+public let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2: DPI_AWARENESS_CONTEXT =
+    DPI_AWARENESS_CONTEXT(bitPattern: -4)!
+public let DPI_AWARENESS_CONTEXT_UNAWARE_GDISCALED: DPI_AWARENESS_CONTEXT =
+    DPI_AWARENESS_CONTEXT(bitPattern: -5)!
+
 // Swift Convenience
 public extension FILETIME {
   var time_t: time_t {