Makes instant throw out the first navigation when merging navigation

stacks. This is because the first navigation is for the home page, and
generally we don't want that in the navigation stack.

I kept the remove first entry functionality in CopyStateFromAndPrune
as its easy to use wrong and I don't want to open up a general API.

BUG=74945
TEST=see bug
R=brettw@chromium.org

Review URL: http://codereview.chromium.org/6709039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@78880 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 11 insertions, 0 deletions

diff --git a/chrome/browser/instant/instant_controller.cc b/chrome/browser/instant/instant_controller.cc
index c7b7494..4949783 100644
--- a/chrome/browser/instant/instant_controller.cc
+++ b/chrome/browser/instant/instant_controller.cc
@@ -234,7 +234,18 @@ bool InstantController::IsCurrent() {
 void InstantController::CommitCurrentPreview(InstantCommitType type) {
   DCHECK(loader_manager_.get());
   DCHECK(loader_manager_->current_loader());
+  bool showing_instant =
+      loader_manager_->current_loader()->is_showing_instant();
   TabContentsWrapper* tab = ReleasePreviewContents(type);
+  // If the loader was showing an instant page then it's navigation stack is
+  // something like: search-engine-home-page (eg google.com) search-term1
+  // search-term2 .... Each search-term navigation corresponds to the page
+  // deciding enough time has passed to commit a navigation. We don't want the
+  // searche-engine-home-page navigation in this case so we pass true to
+  // CopyStateFromAndPrune to have the search-engine-home-page navigation
+  // removed.
+  tab->controller().CopyStateFromAndPrune(
+      &tab_contents_->controller(), showing_instant);
   delegate_->CommitInstant(tab);
   CompleteRelease(tab->tab_contents());
 }