Makes text input extensions available in guest session on CrOS.

The behavioral changes are:

1) Creates background pages of extensions in guest session even if the extension is not "split" mode.  Since the guest session has only the off-the-record context and does not have a regular context, we should treat the off-the-record context like the default regular context.  Even if the extension is "spanning" mode, creates a background page for the off-the-record context in guest session.  Otherwise, extensions in guest session cannot have a background page.

2) Passs key events, etc. to the off-the-record context regardless of whether extensions are enabled in incognito mode or not.  The reason is the same.  We should treat the off-the-record context as the default regular context in guest session.

BUG=339318
TEST=Done manually.  1) Log in as guest, 2) Add Japanese language and enable Google Japanese Input, 3) Activate one of Japanese input method, 4) Type something.

Review URL: https://codereview.chromium.org/177533002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254481 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 13 insertions, 3 deletions

diff --git a/extensions/browser/extensions_browser_client.h b/extensions/browser/extensions_browser_client.h
index 08ffa58..51cff43 100644
--- a/extensions/browser/extensions_browser_client.h
+++ b/extensions/browser/extensions_browser_client.h
@@ -70,7 +70,7 @@ class ExtensionsBrowserClient {
       content::BrowserContext* context) = 0;
 
   // Returns true if |context| corresponds to a guest session.
-  virtual bool IsGuestSession(content::BrowserContext* context) = 0;
+  virtual bool IsGuestSession(content::BrowserContext* context) const = 0;
 
   // Returns true if |extension_id| can run in an incognito window.
   virtual bool IsExtensionIncognitoEnabled(
diff --git a/extensions/browser/process_manager.cc b/extensions/browser/process_manager.cc
index c2db585..721bc14 100644
--- a/extensions/browser/process_manager.cc
+++ b/extensions/browser/process_manager.cc
@@ -177,11 +177,21 @@ struct ProcessManager::BackgroundPageData {
 
 // static
 ProcessManager* ProcessManager::Create(BrowserContext* context) {
+  ExtensionsBrowserClient* client = ExtensionsBrowserClient::Get();
+  if (client->IsGuestSession(context)) {
+    // In the guest session, there is a single off-the-record context.  Unlike
+    // a regular incognito mode, background pages of extensions must be
+    // created regardless of whether extensions use "spanning" or "split"
+    // incognito behavior.
+    BrowserContext* original_context = client->GetOriginalContext(context);
+    return new ProcessManager(context, original_context);
+  }
+
   if (context->IsOffTheRecord()) {
-    BrowserContext* original_context =
-        ExtensionsBrowserClient::Get()->GetOriginalContext(context);
+    BrowserContext* original_context = client->GetOriginalContext(context);
     return new IncognitoProcessManager(context, original_context);
   }
+
   return new ProcessManager(context, context);
 }