Add public APIs for undo / redo in forms.

Add FORM_CanUndo(), FORM_CanRedo(), FORM_Undo(), and FORM_Redo().

BUG=chromium:764260

Change-Id: I1d9ea67152d9b35d9b8e1d7ef7d019706fdfa30a
Reviewed-on: https://pdfium-review.googlesource.com/30872
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/fpdfsdk/pwl/cpwl_combo_box.cpp b/fpdfsdk/pwl/cpwl_combo_box.cpp
index 1576b022fd..2e6e56c52b 100644
--- a/fpdfsdk/pwl/cpwl_combo_box.cpp
+++ b/fpdfsdk/pwl/cpwl_combo_box.cpp
@@ -196,6 +196,22 @@ void CPWL_ComboBox::ReplaceSelection(const WideString& text) {
     m_pEdit->ReplaceSelection(text);
 }
 
+bool CPWL_ComboBox::CanUndo() {
+  return m_pEdit && m_pEdit->CanUndo();
+}
+
+bool CPWL_ComboBox::CanRedo() {
+  return m_pEdit && m_pEdit->CanRedo();
+}
+
+bool CPWL_ComboBox::Undo() {
+  return m_pEdit && m_pEdit->Undo();
+}
+
+bool CPWL_ComboBox::Redo() {
+  return m_pEdit && m_pEdit->Redo();
+}
+
 WideString CPWL_ComboBox::GetText() {
   return m_pEdit ? m_pEdit->GetText() : WideString();
 }