[Password Manager] Add UMA stats to track interaction with synced accounts.

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 b7b146eba4565f1b0f42e6b0ef26e0f562119066..36ac58175eb3d7bb4a0516beca3d321f935414b6 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -19324,6 +19324,16 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="PasswordManager.SyncingAccountState"
+    enum="PasswordManagerSyncingAccountState">
+  <owner>gcasto@chromium.org</owner>
+  <owner>vabr@chromium.org</owner>
+  <summary>
+    Information about the user's current sync status crossed with whether their
+    synced password is saved.
+  </summary>
+</histogram>
+
 <histogram name="PasswordManager.TimesGeneratedPasswordUsed">
   <owner>dubroy@chromium.org</owner>
   <owner>vabr@chromium.org</owner>
@@ -43816,6 +43826,18 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="2" label="Match"/>
 </enum>
 
+<enum name="PasswordManagerSyncingAccountState" type="int">
+  <summary>
+    The value is a combination of the current sync state and if the user has
+    their sync password saved.
+  </summary>
+  <int value="0" label="Not Syncing/Sync password not saved"/>
+  <int value="1"
+      label="Not Syncing/Sync pasword saved. This value should not happen."/>
+  <int value="2" label="Syncing/Sync password not saved"/>
+  <int value="3" label="Syncing/Sync password saved"/>
+</enum>
+
 <enum name="PasswordManagerUIDismissalReason" type="int">
   <int value="0" label="Bubble lost focus / No infobar interaction"/>
   <int value="1" label="Clicked 'Save'"/>