DebugVisualizers: Fix base::Optional

r531722 (crrev.com/c/883946) renamed `is_null_` to `is_populated_`.
This patch fixes chrome.nativs to match to the new name.

Change-Id: Ief8bb4faf90b94a6ca1a4dbd61a5f37bce37273b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1584519
Auto-Submit: Koji Ishii <kojii@chromium.org>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#654110}
diff --git a/tools/win/DebugVisualizers/chrome.natvis b/tools/win/DebugVisualizers/chrome.natvis
index 57a7b62..80cd0ac 100644
--- a/tools/win/DebugVisualizers/chrome.natvis
+++ b/tools/win/DebugVisualizers/chrome.natvis
@@ -22,8 +22,11 @@
     </Expand>
   </Type>
   <Type Name="base::Optional&lt;*&gt;">
-    <DisplayString Condition="storage_.is_null_">(null)</DisplayString>
+    <DisplayString Condition="!storage_.is_populated_">(null)</DisplayString>
     <DisplayString>{storage_.value_}</DisplayString>
+    <Expand>
+      <Item Name="Value" Condition="storage_.is_populated_">storage_.value_</Item>
+    </Expand>
   </Type>
   <Type Name="base::RefCounted&lt;*&gt;">
     <DisplayString>RefCount: {ref_count_}</DisplayString>