Revert "Disabling AccessibilityService sample from build system."

This re-enables the AccessibilityService sample.

This reverts commit ca9d51b.

Author: tjohns

Android.mk

@@ -388,6 +388,8 @@ sample_dir := development/samples
 # (see development/build/sdk.atree)
 web_docs_sample_code_flags := \
 		-hdf android.hasSamples 1 \
+		-samplecode $(sample_dir)/AccessibilityService \
+		            resources/samples/AccessibilityService "Accessibility Service" \
 		-samplecode $(sample_dir)/ApiDemos \
 		            resources/samples/ApiDemos "API Demos" \
 		-samplecode $(sample_dir)/BackupRestore \