Adding TabRestore PLM UMA

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index f5d4032aa24dbd8c475312ebe7874911464a308d..ef62910182425d82c8d8b1677cab6b4a0eef563c 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -117624,6 +117624,16 @@ value.
       name="PageLoad.PaintTiming.ParseStartToFirstContentfulPaint"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="PageLoadMetricsClientsTabRestore" separator="."
+    ordering="prefix">
+  <suffix name="Clients.TabRestore"
+      label="PageLoadMetrics that are a result of a navigation caused by a
+             tab restore."/>
+  <affected-histogram name="PageLoad.Experimental.Bytes.Cache"/>
+  <affected-histogram name="PageLoad.Experimental.Bytes.Network"/>
+  <affected-histogram name="PageLoad.Experimental.Bytes.Total"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="PageLoadMetricsLoadType" separator=".">
   <suffix name="LoadType.Reload" label="Restricted to reloaded pages."/>
   <suffix name="LoadType.ForwardBackNavigation"