Reland of Add errors for declarations which conflict with catch parameters.

test/mjsunit/es6/block-sloppy-function.js

Index: test/mjsunit/es6/block-sloppy-function.js
diff --git a/test/mjsunit/es6/block-sloppy-function.js b/test/mjsunit/es6/block-sloppy-function.js
index e5f244774f673942a382c66703865ee33dfe758d..9a854ac272714ed307d2cd264f935508b639080f 100644
--- a/test/mjsunit/es6/block-sloppy-function.js
+++ b/test/mjsunit/es6/block-sloppy-function.js
@@ -455,6 +455,45 @@
   assertEquals(4, f());
 })();
 
+// B.3.5 interacts with B.3.3 to allow this.
+(function hoistingThroughSimpleCatch() {
+  assertEquals(undefined, f);
+
+  try {
+    throw 0;
+  } catch(f) {
+    {
+      assertEquals(4, f());
+
+      function f() {
+        return 4;
+      }
+
+      assertEquals(4, f());
+    }
+  }
+
+  assertEquals(4, f());
+})();
+
+(function noHoistingThroughComplexCatch() {
+  try {
+    throw 0;
+  } catch({f}) {
+    {
+      assertEquals(4, f());
+
+      function f() {
+        return 4;
+      }
+
+      assertEquals(4, f());
+    }
+  }
+
+  assertThrows(()=>f, ReferenceError);
+})();
+
 // Test that hoisting from blocks does happen in global scope
 function globalHoisted() { return 0; }
 {