Implementing TabManager extensions API Discard Function.

chrome/browser/extensions/api/tabs/tabs_api.cc

Index: chrome/browser/extensions/api/tabs/tabs_api.cc
diff --git a/chrome/browser/extensions/api/tabs/tabs_api.cc b/chrome/browser/extensions/api/tabs/tabs_api.cc
index 082822b843de360c5af776ec9653ec3abb9dad99..ff8e9390c82c74ea1fea43cc1857cd93b0762bcf 100644
--- a/chrome/browser/extensions/api/tabs/tabs_api.cc
+++ b/chrome/browser/extensions/api/tabs/tabs_api.cc
@@ -2168,4 +2168,39 @@ bool TabsGetZoomSettingsFunction::RunAsync() {
   return true;
 }
 
+bool TabsDiscardFunction::RunSync() {
+  std::unique_ptr<tabs::Discard::Params> params(
+      tabs::Discard::Params::Create(*args_));
+  EXTENSION_FUNCTION_VALIDATE(params);
+
+  WebContents* contents = nullptr;
+  // If |tab_id| is given, find the web_contents respective to it.
+  // Otherwise invokes discard function in TabManager with null web_contents

[Georges Khalil, 2016/07/19 19:39:45]

nit: invokes -> invoke

[Anderson Silva, 2016/07/19 20:28:42]

Done.

+  // that will discard the least important tab.
+  if (params->tab_id) {
+    int tab_id = *params->tab_id;
+    if (!GetTabById(tab_id, GetProfile(), include_incognito(), nullptr, nullptr,
+                    &contents, nullptr, &error_))

[Georges Khalil, 2016/07/19 19:39:45]

nit: braces.

[Anderson Silva, 2016/07/19 20:28:42]

Done.

+      return false;
+  }
+
+  memory::TabManager* tab_manager = g_browser_process->GetTabManager();
+  if (!tab_manager)
+    return false;
+
+  bool success = true;
+  contents = tab_manager->DiscardTabByExtension(contents);
+  if (!contents)
+    success = false;

[Georges Khalil, 2016/07/19 19:39:45]

This can be a single line:

bool success = !!contents;

[Anderson Silva, 2016/07/19 20:28:42]

Done.

+
+  if (!has_callback())
+    return true;
+
+  std::unique_ptr<api::tabs::Tab> tab(new api::tabs::Tab);

[Georges Khalil, 2016/07/19 19:39:45]

A small comment would be good here, to explain how the callback works.

[Anderson Silva, 2016/07/19 20:28:42]

Done.

+  if (success)
+    tab = ExtensionTabUtil::CreateTabObject(contents);
+  results_ = api::tabs::Discard::Results::Create(*tab, success);
+  return true;
+}
+
 }  // namespace extensions