fix corner case in pure_getters (#4449)

fixes #4448

lib/compress.js

@@ -358,6 +358,7 @@ merge(Compressor.prototype, {
 
     function is_arguments(def) {
         if (def.name != "arguments") return false;
+        if (!def.scope.uses_arguments) return false;
         var orig = def.orig;
         return orig.length == 1 && orig[0] instanceof AST_SymbolFunarg;
     }

test/compress/arrows.js

@@ -587,3 +587,32 @@ issue_4401: {
     ]
     node_version: ">=4"
 }
+
+issue_4448: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        var A;
+        try {
+            (arguments => {
+                arguments[0];
+            })(A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var A;
+        try {
+            (arguments => {
+                arguments[0];
+            })(A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}