Merge to XFA: Cleanup: Remove CFFL_IFormFiller::GetCommitKey() that always returns 0.

Remove callers and related code that all just pass zeros around.

Also remove CFFL_IFormFiller::GetKeyDown().

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1149623012.

(cherry picked from commit 35c3163d55bebea8095474181f807ddfb2f4f806)

Review URL: https://codereview.chromium.org/1175083003.
diff --git a/fpdfsdk/src/fsdk_actionhandler.cpp b/fpdfsdk/src/fsdk_actionhandler.cpp
index d427686..55abd73 100644
--- a/fpdfsdk/src/fsdk_actionhandler.cpp
+++ b/fpdfsdk/src/fsdk_actionhandler.cpp
@@ -654,7 +654,7 @@
 		pContext->OnField_Blur(data.bModifier, data.bShift, pFormField, data.sValue);
 		break;
 	case CPDF_AAction::KeyStroke:
-		pContext->OnField_Keystroke(data.nCommitKey, data.sChange, data.sChangeEx, data.bKeyDown,
+		pContext->OnField_Keystroke(data.sChange, data.sChangeEx, data.bKeyDown,
 			data.bModifier, data.nSelEnd, data.nSelStart, data.bShift, pFormField, data.sValue,
 			data.bWillCommit, data.bFieldFull, data.bRC);
 		break;