Replace two ASSERT()s for HashMap iterators with DCHECK_NE()s.

third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp

Index: third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp
diff --git a/third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp b/third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp
index 8a9167c7ae27c6485a4b7458a24f49504c3fb583..7380b2970a1fd50c2b864a800d004627279cc5dd 100644
--- a/third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp
+++ b/third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp
@@ -143,7 +143,7 @@ void RadioButtonGroup::requiredAttributeChanged(HTMLInputElement* button)
 {
     DCHECK_EQ(button->type(), InputTypeNames::radio);
     auto it = m_members.find(button);
-    ASSERT(it != m_members.end());
+    DCHECK_NE(it, m_members.end());
     bool wasValid = isValid();
     // Synchronize the 'required' flag for the button, along with
     // updating the overall count.