Move FrameHostMsg_GoToEntryAtOffset to mojo

This CL changes FrameHostMsg_GoToEntryAtOffset so that it is
implemented in the LocalFrameHost interface.

It removes WebLocalFrameClient::NavigateBackForwardSoon() from
web_local_frame_client.h since LocalFrameClientImpl have access to
mojom::blink::LocalFrameHost.

Bug: 1039286
Change-Id: If565c4fffb3f785d3518dc38171cf7092c7ef30d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2000267
Commit-Queue: Julie Kim <[email protected]>
Reviewed-by: Dave Tapuska <[email protected]>
Reviewed-by: Kinuko Yasuda <[email protected]>
Cr-Commit-Position: refs/heads/master@{#733150}
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 0e16aab..5253b94 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -902,7 +902,6 @@
                         OnDidDisplayContentWithCertificateErrors)
     IPC_MESSAGE_HANDLER(FrameHostMsg_DidRunContentWithCertificateErrors,
                         OnDidRunContentWithCertificateErrors)
-    IPC_MESSAGE_HANDLER(FrameHostMsg_GoToEntryAtOffset, OnGoToEntryAtOffset)
     IPC_MESSAGE_HANDLER(FrameHostMsg_UpdateFaviconURL, OnUpdateFaviconURL)
 #if BUILDFLAG(ENABLE_PLUGINS)
     IPC_MESSAGE_HANDLER(FrameHostMsg_PepperInstanceCreated,
@@ -4879,7 +4878,7 @@
 }
 
 void WebContentsImpl::OnGoToEntryAtOffset(RenderFrameHostImpl* source,
-                                          int offset,
+                                          int32_t offset,
                                           bool has_user_gesture) {
   // Non-user initiated navigations coming from the renderer should be ignored
   // if there is an ongoing browser-initiated navigation.