[feedback] add more reboot reasons

We are increasing the max_event_code from 1 to 7. This should be ok as
we are still below 8. The underlying bit string works in increment of 8.

Bug: 6647

COBALT_BACKWARDS_INCOMPATIBLE_CHANGE_DATA_CORRUPTION_POSSIBLE=ok

Change-Id: I59fe1fc015cf0f91b7639c46e14c773d888be532
diff --git a/fuchsia/feedback/metrics.yaml b/fuchsia/feedback/metrics.yaml
index 42c4126..4aa175e 100644
--- a/fuchsia/feedback/metrics.yaml
+++ b/fuchsia/feedback/metrics.yaml
@@ -8,8 +8,6 @@
 # reboot
 #
 # Count of times the system rebooted.
-# Currently we only track crashes and OOMs (Out Of Memory).
-# There is a plan to add additional types.
 # We send the event upon reboot.
 #####################################################################
 - id: 1
@@ -20,12 +18,18 @@
       event_codes:
         0: KernelPanic
         1: OOM
-      max_event_code: 1
+        2: Clean
+        3: Cold
+        4: Unknown
+        5: HardwareWatchdog
+        6: SoftwareWatchdog
+        7: Brownout
+      max_event_code: 7
   reports:
       #####################################################################
       # reboot_event_counts
       #
-      # Count of each of the types of reboot occurances.
+      # Count of each of the types of reboot occurrences.
       #####################################################################
     - report_name: reboot_event_counts
       id: 3671940974 # legacy long report_id