SEGV in CFX_BaseSegmentedArray::Iterate() when CS has malformed dictionary.

core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp

Index: core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
index fc4e282f10ef8b8b601304144e55d3a03042b35c..b6bf7950ff5c026f127fea88278cbc4466c81a31 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
@@ -438,6 +438,9 @@ public:
 FX_BOOL CPDF_LabCS::v_Load(CPDF_Document* pDoc, CPDF_Array* pArray)
 {
     CPDF_Dictionary* pDict = pArray->GetDict(1);
+    if (!pDict) {
+        return FALSE;
+    }
     CPDF_Array* pParam = pDict->GetArray(FX_BSTRC("WhitePoint"));
     int i;
     for (i = 0; i < 3; i ++) {