Update to use CFX_Rect{F} and CFX_Matrix constructors.

This Cl updates the code to use the constructors instead of creating an
empty object and calling Set(). It also removes the various memsets of
the CFX_Rect{F} classes.

Change-Id: I6e20cec00866a38372858dcba5a30d31103172e4
Reviewed-on: https://pdfium-review.googlesource.com/2550
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: Nicolás Peña <npm@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
diff --git a/fpdfsdk/formfiller/cffl_formfiller.cpp b/fpdfsdk/formfiller/cffl_formfiller.cpp
index 281057a..71feb54 100644
--- a/fpdfsdk/formfiller/cffl_formfiller.cpp
+++ b/fpdfsdk/formfiller/cffl_formfiller.cpp
@@ -395,6 +395,7 @@
     if (pPrivateData->pPageView) {
       CFX_Matrix mtPageView;
       pPrivateData->pPageView->GetCurrentMatrix(mtPageView);
+
       CFX_Matrix mt = GetCurMatrix();
       mt.Concat(mtPageView);