create two layout pass reason flexLayout and flexMeasure instead of flex

Summary:
We had flex as a reason for both layout and measure. Now creating separating reason flexLayout and flexMeasure in this diff.

Also changed ordering of items in Enum to group layout and measure reasons

Reviewed By: davidaurelio

Differential Revision: D16562350

fbshipit-source-id: 75501f9d4dde0974009193b3991a8acc97b02ad0

yoga/event/event.cpp

@@ -16,18 +16,20 @@ const char* LayoutPassReasonToString(const LayoutPassReason value) {
   switch (value) {
     case LayoutPassReason::kInitial:
       return "initial";
-    case LayoutPassReason::kMeasureChild:
-      return "measure";
-    case LayoutPassReason::kAbsMeasureChild:
-      return "abs_measure";
-    case LayoutPassReason::kFlex:
-      return "flex";
     case LayoutPassReason::kAbsLayout:
       return "abs_layout";
     case LayoutPassReason::kStretch:
       return "stretch";
     case LayoutPassReason::kMultilineStretch:
       return "multiline_stretch";
+    case LayoutPassReason::kFlexLayout:
+      return "flex_layout";
+    case LayoutPassReason::kMeasureChild:
+      return "measure";
+    case LayoutPassReason::kAbsMeasureChild:
+      return "abs_measure";
+    case LayoutPassReason::kFlexMeasure:
+      return "flex_measure";
     default:
       return "unknown";
   }