Fix blink.natvis for String and NGFragmentItem

This patch fixes following issues in blink.natvis:
1. Fix the incorrect condition for the "bare" view of
   |StringImpl|.
2. Fix the order of `<DisplayString>` for |StringImpl|.
   The `<DisplayString>` element without `Condition` must come
   the last, causing a warning message when natvis diagnostic
   message is enabled.
3. At some point VisualStudio stopped displaying anonymous
   union, and that the natvis failed to display
   |NGFragmentItem|. Removed members of the anonymous union,
   instead, added |Type| and a few other members.

Checked with natvis diagnostic message turned on.

Change-Id: I25cebc1695434d712d7d5a1a816ae272120d6abb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2467503Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816912}

tools/win/DebugVisualizers/blink.natvis

@@ -27,12 +27,12 @@
     <DisplayString IncludeView="bare"
                    Condition="*(int*)&amp;hash_and_flags_ &amp; 1">
         {(this+1),[length_]sb}</DisplayString>
-    <DisplayString>[{length_}] {(this+1),[length_]s}</DisplayString>
     <DisplayString IncludeView="bare"
-                   Condition="*(int*)&amp;hash_and_flags_ &amp; 1">
+                   Condition="!(*(int*)&amp;hash_and_flags_ &amp; 1)">
         {(this+1),[length_]sub}</DisplayString>
-    <DisplayString Condition="(*(int*)&amp;hash_and_flags_ &amp; 1)==0">
-        [{length_}] {(this+1),[length_]su}</DisplayString>
+    <DisplayString Condition="*(int*)&amp;hash_and_flags_ &amp; 1">
+        [{length_}] {(this+1),[length_]s}</DisplayString>
+    <DisplayString>[{length_}] {(this+1),[length_]su}</DisplayString>
     <Expand>
       <Item Name="Length">length_</Item>
       <Item Name="AsciiText"
@@ -288,14 +288,13 @@
   </Type>
   <Type Name="blink::NGFragmentItem">
     <Expand>
-      <Item Name="Text" Condition="type_ == 0">text_</Item>
+      <Item Name="Type">(blink::NGFragmentItem::ItemType)type_</Item>
       <Item Name="TextType" Condition="type_ == 0">(blink::NGTextType)sub_type_</Item>
-      <Item Name="GeneratedText" Condition="type_ == 1">generated_text_</Item>
-      <Item Name="Line" Condition="type_ == 2">line_</Item>
       <Item Name="LineBoxType" Condition="type_ == 2">(NGPhysicalLineBoxFragment::NGLineBoxType)sub_type_</Item>
-      <Item Name="Box" Condition="type_ == 3">box_</Item>
       <Item Name="layout_object_">layout_object_</Item>
       <Item Name="rect_">rect_</Item>
+      <Item Name="ink_overflow_type_">(NGInkOverflow::Type)ink_overflow_type_</Item>
+      <Item Name="is_dirty_">is_dirty_</Item>
     </Expand>
   </Type>
   <Type Name="blink::NGFragmentItems">