Add an originating element for AutoFactory types

RELNOTES=n/a

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=248722215

2 files changed, 7 insertions, 1 deletions

diff --git a/factory/src/main/java/com/google/auto/factory/processor/FactoryDescriptor.java b/factory/src/main/java/com/google/auto/factory/processor/FactoryDescriptor.java
index 8815ce5e..2ffad953 100644
--- a/factory/src/main/java/com/google/auto/factory/processor/FactoryDescriptor.java
+++ b/factory/src/main/java/com/google/auto/factory/processor/FactoryDescriptor.java
@@ -56,6 +56,10 @@ abstract class FactoryDescriptor {
   abstract boolean allowSubclasses();
   abstract ImmutableMap<Key, ProviderField> providers();
 
+  final AutoFactoryDeclaration declaration() {
+    return Iterables.getFirst(methodDescriptors(), null).declaration();
+  }
+
   private static class UniqueNameSet {
     private final Set<String> uniqueNames = new HashSet<String>();
 
diff --git a/factory/src/main/java/com/google/auto/factory/processor/FactoryWriter.java b/factory/src/main/java/com/google/auto/factory/processor/FactoryWriter.java
index 5ceb82eb..61058470 100644
--- a/factory/src/main/java/com/google/auto/factory/processor/FactoryWriter.java
+++ b/factory/src/main/java/com/google/auto/factory/processor/FactoryWriter.java
@@ -67,7 +67,9 @@ final class FactoryWriter {
   void writeFactory(final FactoryDescriptor descriptor)
       throws IOException {
     String factoryName = getSimpleName(descriptor.name()).toString();
-    TypeSpec.Builder factory = classBuilder(factoryName);
+    TypeSpec.Builder factory =
+        classBuilder(factoryName)
+            .addOriginatingElement(descriptor.declaration().targetType());
     generatedAnnotationSpec(
             elements,
             sourceVersion,