AutoDiscardable property support on Chrome Extensions Tabs API.

chrome/common/extensions/api/tabs.json

Index: chrome/common/extensions/api/tabs.json
diff --git a/chrome/common/extensions/api/tabs.json b/chrome/common/extensions/api/tabs.json
index 1f64ec11977595430a6431c66487b16e9f267e05..105d038ecc13feac93d07f7137445feb223dd43a 100644
--- a/chrome/common/extensions/api/tabs.json
+++ b/chrome/common/extensions/api/tabs.json
@@ -52,6 +52,7 @@
           "pinned": {"type": "boolean", "description": "Whether the tab is pinned."},
           "audible": {"type": "boolean", "optional": true, "description": "Whether the tab has produced sound over the past couple of seconds (but it might not be heard if also muted). Equivalent to whether the speaker audio indicator is showing."},
           "discarded": {"type": "boolean", "description": "Whether the tab is discarded. A discarded tab is one whose content has been unloaded from memory, but is still visible in the tab strip. Its content gets reloaded the next time it's activated."},
+          "autoDiscardable":  {"type": "boolean", "description": "Whether the tab is auto-discardable. An auto-discardable tab is eligible for discarding when memory resources are low."},

[Devlin, 2016/08/02 22:48:14]

Saying "whether the tab is auto-discardable. <definition of auto-discardable>"
could probably be replaced here with "whether the tab is <definition of
auto-discardable>".  Also, aren't non-auto-discardable tabs eligible for
discarding from the discard() method?  If so, maybe we should change this to
something like "can be discarded automatically by the browser when resources are
low."

[Anderson Silva, 2016/08/03 14:47:41]

Yes, you're right, non-auto-discardable tabs can be discarded by discard(). I'll
update the description.

           "mutedInfo": {"$ref": "MutedInfo", "optional": true, "description": "Current tab muted state and the reason for the last state change."},
           "url": {"type": "string", "optional": true, "description": "The URL the tab is displaying. This property is only present if the extension's manifest includes the <code>\"tabs\"</code> permission."},
           "title": {"type": "string", "optional": true, "description": "The title of the tab. This property is only present if the extension's manifest includes the <code>\"tabs\"</code> permission."},
@@ -451,7 +452,12 @@
               "discarded": {
                 "type": "boolean",
                 "optional": true,
-                "description": "Whether the tab is discarded. A discarded tab is one whose content has been unloaded from memory, but is still visible in the tab strip. Its content gets reloaded the next time it's activated."
+                "description": "Whether the tabs are discarded. A discarded tab is one whose content has been unloaded from memory, but is still visible in the tab strip. Its content gets reloaded the next time it's activated."
+              },
+              "autoDiscardable": {
+                "type": "boolean",
+                "optional": true,
+                "description": "Whether the tabs are auto-discardable. An auto-discardable tab is eligible for discarding when memory resources are low."
               },
               "currentWindow": {
                 "type": "boolean",
@@ -605,6 +611,11 @@
                 "minimum": 0,
                 "optional": true,
                 "description": "The ID of the tab that opened this tab. If specified, the opener tab must be in the same window as this tab."
+              },
+              "autoDiscardable": {
+                "type": "boolean",
+                "optional": true,
+                "description": "Whether the tab should be auto-discardable. An auto-discardable tab is eligible for discarding when memory resources are low."
               }
             }
           },
@@ -986,6 +997,11 @@
                 "optional": true,
                 "description": "The tab's new discarded state."
               },
+              "autoDiscardable": {
+                "type": "boolean",
+                "optional": true,
+                "description": "The tab's new auto-discardable state."
+              },
               "mutedInfo": {
                 "$ref": "MutedInfo",
                 "optional": true,