Report error instead of exception for getter or setter in export obje…

…ct literal.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=157834460

src/com/google/javascript/jscomp/ProcessCommonJSModules.java

@@ -53,6 +53,11 @@ public final class ProcessCommonJSModules implements CompilerPass {
           "Suspicious re-assignment of \"exports\" variable."
               + " Did you actually intend to export something?");
 
+  public static final DiagnosticType UNSUPPORTED_GETTER_SETTER_METHOD =
+      DiagnosticType.warning(
+          "JSC_UNSUPPORTED_GETTER_SETTER_METHOD",
+          "Getter and setter methods are unsupported.");
+
   private final Compiler compiler;
   private final boolean reportDependencies;
 
@@ -863,10 +868,14 @@ private void expandObjectLitAssignment(NodeTraversal t, Node export) {
 
       Node rValue = NodeUtil.getRValueOfLValue(export);
       Node key = rValue.getFirstChild();
+
       while (key != null) {
         Node lhs;
         if (key.isQuotedString()) {
           lhs = IR.getelem(export.cloneTree(), IR.string(key.getString()));
+        } else if (key.isGetterDef() || key.isSetterDef()) {
+          compiler.report(t.makeError(key, UNSUPPORTED_GETTER_SETTER_METHOD));
+          return;
         } else {
           lhs = IR.getprop(export.cloneTree(), IR.string(key.getString()));
         }

test/com/google/javascript/jscomp/ProcessCommonJSModulesTest.java

@@ -829,4 +829,14 @@ public void testAbsoluteImportsWithModuleRoots() {
                     "var name = module$mod$name;",
                     "(function() { module$mod$name(); })();"))));
   }
+
+  public void testIssue2510() {
+    setFilename("test");
+    testModules(
+        "module.exports = {a: function() {return 1}};",
+        LINE_JOINER.join(
+            "goog.provide('module$test');",
+            "/** @const */ var module$test = {};",
+            "module$test.a = function() {return 1};"));
+  }
 }