tracing: Add private footprint

tracing/tracing/metrics/system_health/memory_metric_test.html

Index: tracing/tracing/metrics/system_health/memory_metric_test.html
diff --git a/tracing/tracing/metrics/system_health/memory_metric_test.html b/tracing/tracing/metrics/system_health/memory_metric_test.html
index 7d43d8a695c36156d48bbf76d9574746ac9f8271..c07c7fd31b22bdefa027aa40989c006efef0656b 100644
--- a/tracing/tracing/metrics/system_health/memory_metric_test.html
+++ b/tracing/tracing/metrics/system_health/memory_metric_test.html
@@ -398,7 +398,8 @@ tr.b.unittest.testSuite(function() {
     ];
     pmdBrowser1.totals = {
       residentBytes: 200,
-      peakResidentBytes: 230
+      peakResidentBytes: 230,
+      privateFootprintBytes: 240,
     };
     const pmdRendererA1 = addProcessMemoryDump(gmd1, pRendererA, {ts: 20});
     pmdRendererA1.memoryAllocatorDumps = (function() {
@@ -645,8 +646,8 @@ tr.b.unittest.testSuite(function() {
     'memory:chrome:all_processes:reported_by_os:resident_size': {
       value: [200, 0, 0, 0],
       unit: sizeInBytes_smallerIsBetter,
-      description: 'total resident set size (RSS) reported by the OS for all ' +
-          'processes in Chrome'
+      description: 'total resident set size (RSS) reported by the OS for all' +
+          ' processes in Chrome'
     },
     'memory:chrome:all_processes:reported_by_os:peak_resident_size': {
       value: [230, 0, 0, 0],
@@ -654,6 +655,12 @@ tr.b.unittest.testSuite(function() {
       description: 'total peak resident set size reported by the OS for all ' +
           'processes in Chrome'
     },
+    'memory:chrome:all_processes:reported_by_os:private_footprint_size': {
+      value: [240, 0, 0, 0],
+      unit: sizeInBytes_smallerIsBetter,
+      description: 'total private footprint size reported by the OS for all ' +
+          'processes in Chrome'
+    },
     'memory:chrome:all_processes:reported_by_os:system_memory:resident_size': {
       value: [200, 0, 0, 0],
       unit: sizeInBytes_smallerIsBetter,
@@ -667,6 +674,12 @@ tr.b.unittest.testSuite(function() {
       description: 'total peak resident set size of system memory (RAM) ' +
               'used by all processes in Chrome'
     },
+    'memory:chrome:all_processes:reported_by_os:system_memory:private_footprint_size': { // eslint-disable-line max-len
+      value: [240, 0, 0, 0],
+      unit: sizeInBytes_smallerIsBetter,
+      description: 'total private footprint size of system memory (RAM) ' +
+          'used by all processes in Chrome'
+    },
     'memory:chrome:all_processes:reported_by_chrome:gpu:effective_size': {
       value: [30, 0, 300, 0],
       unit: sizeInBytes_smallerIsBetter,
@@ -857,6 +870,19 @@ tr.b.unittest.testSuite(function() {
       description: 'total peak resident set size of system memory (RAM) ' +
               'used by the browser process in Chrome'
     },
+    'memory:chrome:browser_process:reported_by_os:private_footprint_size': {
+      value: [240, 0, 0, 0],
+      unit: sizeInBytes_smallerIsBetter,
+      description: 'total private footprint size reported by the OS for the ' +
+          'browser process in Chrome'
+    },
+    'memory:chrome:browser_process:reported_by_os:system_memory:private_footprint_size':
+    {
+      value: [240, 0, 0, 0],
+      unit: sizeInBytes_smallerIsBetter,
+      description: 'total private footprint size of system memory (RAM) ' +
+              'used by the browser process in Chrome'
+    },
     'memory:chrome:browser_process:reported_by_os:resident_size': {
       value: [200, 0, 0, 0],
       unit: sizeInBytes_smallerIsBetter,