Non-constraint interfaces for all constrainable interfaces

webrtc/api/mediaconstraintsinterface.cc

Index: webrtc/api/mediaconstraintsinterface.cc
diff --git a/webrtc/api/mediaconstraintsinterface.cc b/webrtc/api/mediaconstraintsinterface.cc
index 51521946f6674ff5d0aa5647ab465fd7f758f973..6d54640472f4a748a230ff8cb72be236e45593b3 100644
--- a/webrtc/api/mediaconstraintsinterface.cc
+++ b/webrtc/api/mediaconstraintsinterface.cc
@@ -129,4 +129,46 @@ bool FindConstraint(const MediaConstraintsInterface* constraints,
   return false;
 }
 
+// As above, but for integers.
+bool FindConstraint(const MediaConstraintsInterface* constraints,
+                    const std::string& key,
+                    int* value,
+                    size_t* mandatory_constraints) {
+  std::string string_value;
+  if (!constraints) {
+    return false;
+  }
+  if (constraints->GetMandatory().FindFirst(key, &string_value)) {
+    if (mandatory_constraints)
+      ++*mandatory_constraints;
+    return rtc::FromString(string_value, value);
+  }
+  if (constraints->GetOptional().FindFirst(key, &string_value)) {
+    return rtc::FromString(string_value, value);
+  }
+  return false;
+}
+
+rtc::Optional<bool> ConstraintToOptionalBool(
+    const MediaConstraintsInterface* constraints,
+    const std::string& key) {
+  bool value;
+  bool present = FindConstraint(constraints, key, &value, nullptr);
+  if (present) {
+    return rtc::Optional<bool>(value);
+  }
+  return rtc::Optional<bool>();
+}
+
+rtc::Optional<int> ConstraintToOptionalInt(
+    const MediaConstraintsInterface* constraints,
+    const std::string& key) {
+  int value;
+  bool present = FindConstraint(constraints, key, &value, nullptr);
+  if (present) {
+    return rtc::Optional<int>(value);
+  }
+  return rtc::Optional<int>();
+}
+
 }  // namespace webrtc