Enable building sdk/avdlauncher in the Win SDK. DO NOT MERGE.

Required by Change-Id Ic651e3c3 in sdk.git

Cherry-pick from master c36df7b12bb5e1e97e39c3576d330af37536b02d

Change-Id: Ic51ad7df01ce1bc926ba69f8a031a060edbf0bd1
diff --git a/core/main.mk b/core/main.mk
index 1f03355..6841b36 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -415,6 +415,7 @@
 	external/zlib \
 	frameworks/base \
 	frameworks/compile \
+	sdk/avdlauncher \
 	sdk/emulator/mksdcard \
 	sdk/sdklauncher \
 	system/core/adb \