Only generate suggested filenames when actually dragging an image.

third_party/WebKit/Source/core/loader/DocumentLoader.cpp

Index: third_party/WebKit/Source/core/loader/DocumentLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
index 613a0e43d29c297520445322580490d01dafa2d4..d4e6c1962a2b861416eaeb346897669cf28003d8 100644
--- a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
@@ -440,7 +440,7 @@ void DocumentLoader::cancelLoadAfterCSPDenied(
   m_request.setURL(blockedURL);
   m_redirectChain.pop_back();
   appendRedirect(blockedURL);
-  m_response = ResourceResponse(blockedURL, "text/html", 0, nullAtom, String());
+  m_response = ResourceResponse(blockedURL, "text/html", 0, nullAtom);
   finishedLoading(monotonicallyIncreasingTime());
 
   return;
@@ -709,8 +709,7 @@ bool DocumentLoader::maybeLoadEmpty() {
   if (m_request.url().isEmpty() &&
       !frameLoader().stateMachine()->creatingInitialEmptyDocument())
     m_request.setURL(blankURL());
-  m_response =
-      ResourceResponse(m_request.url(), "text/html", 0, nullAtom, String());
+  m_response = ResourceResponse(m_request.url(), "text/html", 0, nullAtom);
   finishedLoading(monotonicallyIncreasingTime());
   return true;
 }