Rename CXFA_Box methods to make return clearer

This CL renames the methods in CXFA_Box to make it clearer they can
return nullptr.

Change-Id: I521c0e06af306f69e390a4057cabb7777a0d72f5
Reviewed-on: https://pdfium-review.googlesource.com/22740
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

3 files changed, 14 insertions, 8 deletions

diff --git a/xfa/fxfa/parser/cxfa_box.cpp b/xfa/fxfa/parser/cxfa_box.cpp
index 443362f449..5f8bed9aa1 100644
--- a/xfa/fxfa/parser/cxfa_box.cpp
+++ b/xfa/fxfa/parser/cxfa_box.cpp
@@ -81,7 +81,7 @@ int32_t CXFA_Box::CountEdges() {
   return CountChildren(XFA_Element::Edge, false);
 }
 
-CXFA_Edge* CXFA_Box::GetEdge(int32_t nIndex) {
+CXFA_Edge* CXFA_Box::GetEdgeIfExists(int32_t nIndex) {
   if (nIndex == 0)
     return JSObject()->GetOrCreateProperty<CXFA_Edge>(nIndex,
                                                       XFA_Element::Edge);
@@ -104,15 +104,15 @@ Optional<int32_t> CXFA_Box::GetSweepAngle() {
   return JSObject()->TryInteger(XFA_Attribute::SweepAngle, false);
 }
 
-CXFA_Fill* CXFA_Box::GetFill() const {
+CXFA_Fill* CXFA_Box::GetFillIfExists() const {
   return JSObject()->GetProperty<CXFA_Fill>(0, XFA_Element::Fill);
 }
 
-CXFA_Fill* CXFA_Box::GetOrCreateFill() {
+CXFA_Fill* CXFA_Box::GetOrCreateFillIfPossible() {
   return JSObject()->GetOrCreateProperty<CXFA_Fill>(0, XFA_Element::Fill);
 }
 
-CXFA_Margin* CXFA_Box::GetMargin() {
+CXFA_Margin* CXFA_Box::GetMarginIfExists() {
   return GetChild<CXFA_Margin>(0, XFA_Element::Margin, false);
 }
 
@@ -144,6 +144,8 @@ std::vector<CXFA_Stroke*> CXFA_Box::GetStrokesInternal(bool bNull) {
       corner = JSObject()->GetProperty<CXFA_Corner>(i, XFA_Element::Corner);
     }
 
+    // TODO(dsinclair): If i == 0 and GetOrCreateProperty failed, we can end up
+    // with a null corner in the first position.
     if (corner || i == 0) {
       strokes[j] = corner;
     } else if (!bNull) {
@@ -160,6 +162,8 @@ std::vector<CXFA_Stroke*> CXFA_Box::GetStrokesInternal(bool bNull) {
     else
       edge = JSObject()->GetProperty<CXFA_Edge>(i, XFA_Element::Edge);
 
+    // TODO(dsinclair): If i == 0 and GetOrCreateProperty failed, we can end up
+    // with a null edge in the first position.
     if (edge || i == 0) {
       strokes[j] = edge;
     } else if (!bNull) {
diff --git a/xfa/fxfa/parser/cxfa_box.h b/xfa/fxfa/parser/cxfa_box.h
index c85d0164af..216a981c83 100644
--- a/xfa/fxfa/parser/cxfa_box.h
+++ b/xfa/fxfa/parser/cxfa_box.h
@@ -30,10 +30,10 @@ class CXFA_Box : public CXFA_Node {
   std::tuple<XFA_AttributeEnum, bool, float> Get3DStyle();
 
   int32_t CountEdges();
-  CXFA_Edge* GetEdge(int32_t nIndex);
-  CXFA_Fill* GetFill() const;
-  CXFA_Fill* GetOrCreateFill();
-  CXFA_Margin* GetMargin();
+  CXFA_Edge* GetEdgeIfExists(int32_t nIndex);
+  CXFA_Fill* GetFillIfExists() const;
+  CXFA_Fill* GetOrCreateFillIfPossible();
+  CXFA_Margin* GetMarginIfExists();
 
   std::vector<CXFA_Stroke*> GetStrokes();
 
diff --git a/xfa/fxfa/parser/cxfa_edge.h b/xfa/fxfa/parser/cxfa_edge.h
index 8bf9f6ea28..36fee55624 100644
--- a/xfa/fxfa/parser/cxfa_edge.h
+++ b/xfa/fxfa/parser/cxfa_edge.h
@@ -11,6 +11,8 @@
 
 class CXFA_Edge : public CXFA_Stroke {
  public:
+  static constexpr FX_ARGB kDefaultColor = 0xFF000000;
+
   CXFA_Edge(CXFA_Document* doc, XFA_PacketType packet);
   ~CXFA_Edge() override;
 };