distribution: require start of line, semicolon, open or close curly braces, or */ to appear before [ before treating it as metadata (references #650)

Author: joshtynjala

distribution/src/assembly/syntaxes/AS3.tmLanguage

@@ -1340,7 +1340,7 @@
 		<key>metadata</key>
 		<dict>
 			<key>begin</key>
-			<string>\[\s*\b([A-Za-z_\$][A-Za-z0-9_\$]+)\b</string>
+			<string>(?&lt;=(?:^|;|\}|\{|\*\/)\s*)\[\s*\b([A-Za-z_\$][A-Za-z0-9_\$]+)\b</string>
 			<key>beginCaptures</key>
 			<dict>
 				<key>1</key>