fix typo

Author: mhegazy

src/compiler/declarationEmitter.ts

@@ -1266,7 +1266,7 @@ namespace ts {
                         Diagnostics.Exported_variable_0_has_or_is_using_private_name_1;
                 }
                 // This check is to ensure we don't report error on constructor parameter property as that error would be reported during parameter emit
-                // The only exception here is if the constructor was marked as private. we are not emitting the constructor paramters at all.
+                // The only exception here is if the constructor was marked as private. we are not emitting the constructor parameters at all.
                 else if (node.kind === SyntaxKind.PropertyDeclaration || node.kind === SyntaxKind.PropertySignature ||
                     (node.kind === SyntaxKind.Parameter && hasModifier(node.parent, ModifierFlags.Private))) {
                     // TODO(jfreeman): Deal with computed properties in error reporting.