Remove Google App Engine from documentation (#8038)

* Remove Google App Engine from documentation

Mention removal in release notes.

Part of #8033

5 files changed, 3 insertions, 85 deletions

diff --git a/all/src/main/templates/release-notes.html b/all/src/main/templates/release-notes.html
index aa6b4f962a..d72fee79f5 100644
--- a/all/src/main/templates/release-notes.html
+++ b/all/src/main/templates/release-notes.html
@@ -114,6 +114,7 @@
         <ul><h4>Compatibility and requirements</h4>
             <li>Vaadin Framework now requires Java 8 or later and Servlet 3.0 or later</li>
             <li>Support for older browsers (including Microsoft IE 8-10) and Windows Phone has been dropped</li>
+            <li>Support for Google App Engine has been dropped</li>
             <li><a href="#supportedservers">Supported servers</a></li>
         </ul>
         <ul><h4>New Data Binding API related changes</h4>
diff --git a/documentation/advanced/advanced-gae.asciidoc b/documentation/advanced/advanced-gae.asciidoc
deleted file mode 100644
index 0547f2f134..0000000000
--- a/documentation/advanced/advanced-gae.asciidoc
+++ /dev/null
@@ -1,71 +0,0 @@
----
-title: Google App Engine Integration
-order: 7
-layout: page
----
-
-[[advanced.gae]]
-= Google App Engine Integration
-
-__This section is not yet fully updated to Vaadin 7.__
-
-Vaadin includes support to run Vaadin applications in the Google App Engine
-(GAE). The most essential requirement for GAE is the ability to serialize the
-application state. Vaadin applications are serializable through the
-[classname]#java.io.Serializable# interface.
-
-To run as a GAE application, an application must use
-[classname]#GAEVaadinServlet# instead of [classname]#VaadinServlet#, and of
-course implement the [classname]#java.io.Serializable# interface for all
-persistent classes. You also need to enable session support in
-[filename]#appengine-web.xml# with:
-
-
-[source, xml]
-----
-<sessions-enabled>true</sessions-enabled>
-----
-
-The Vaadin Project wizard can create the configuration files needed for GAE
-deployment. See
-<<dummy/../../../framework/getting-started/getting-started-first-project#getting-started.first-project.creation,"Creating
-the Project">>. When the Google App Engine deployment configuration is selected,
-the wizard will create the project structure following the GAE Servlet
-convention instead of the regular Servlet convention. The main differences are:
-
-* Source directory: [filename]#src/main/java#
-* Output directory: [filename]#war/WEB-INF/classes#
-* Content directory: [filename]#war#
-
-== Rules and Limitations
-
-Running Vaadin applications in Google App Engine has the following rules and
-limitations:
-
-* Avoid using the session for storage, usual App Engine limitations apply (no
-synchronization, that is, it is unreliable).
-
-* Vaadin uses memcache for mutex, the key is of the form
-[parameter]#_vmutex&lt;sessionid&gt;#.
-
-* The Vaadin [classname]#WebApplicationContext# class is serialized separately
-into memcache and datastore; the memcache key is [parameter]#_vac&lt;sessionid&gt;#
-and the datastore entity kind is [parameter]#_vac# with identifiers of the type
-[parameter]#_vac&lt;sessionid&gt;#.
-
-* __Do not__ update the application state when serving an
-[classname]#ConnectorResource# (such as [classname]#ClassResource#.
-[methodname]#getStream()#).
-
-* __Avoid__ (or be very careful when) updating application state in a
-[classname]#TransactionListener# - it is called even when the application is not
-locked and won't be serialized (such as with [classname]#ConnectorResource#),
-and changes can therefore be lost (it should be safe to update things that can
-be safely discarded later, that is, valid only for the current request).
-
-* The application remains locked during uploads - a progress bar is not possible.
-
-
-
-
-
diff --git a/documentation/advanced/chapter-advanced.asciidoc b/documentation/advanced/chapter-advanced.asciidoc
index b14abfdda1..c80ea410f1 100644
--- a/documentation/advanced/chapter-advanced.asciidoc
+++ b/documentation/advanced/chapter-advanced.asciidoc
@@ -16,8 +16,6 @@ include::advanced-shortcuts.asciidoc[leveloffset=+2]
 
 include::advanced-printing.asciidoc[leveloffset=+2]
 
-include::advanced-gae.asciidoc[leveloffset=+2]
-
 include::advanced-security.asciidoc[leveloffset=+2]
 
 include::advanced-navigator.asciidoc[leveloffset=+2]
diff --git a/documentation/application/application-lifecycle.asciidoc b/documentation/application/application-lifecycle.asciidoc
index 219002b414..8ce552c663 100644
--- a/documentation/application/application-lifecycle.asciidoc
+++ b/documentation/application/application-lifecycle.asciidoc
@@ -55,15 +55,7 @@ Serialization requires that the applications are __serializable__, that is, all
 classes implement the [interfacename]#Serializable# interface. All Vaadin
 classes do. If you extend them or implement interfaces, you can provide an
 optional serialization key, which is automatically generated by Eclipse if you
-use it. Serialization is also used for clustering and cloud computing, such as
-with Google App Engine.
-
-ifdef::web[]
-For more about that topic, see
-<<dummy/../../../framework/advanced/advanced-gae#advanced.gae,"Google App Engine
-Integration">>.
-endif::web[]
-
+use it. Serialization is also used for clustering and cloud computing.
 
 
 [[application.lifecycle.servlet-service]]
diff --git a/documentation/getting-started/getting-started-first-project.asciidoc b/documentation/getting-started/getting-started-first-project.asciidoc
index ede6f77841..3262b8a4b1 100644
--- a/documentation/getting-started/getting-started-first-project.asciidoc
+++ b/documentation/getting-started/getting-started-first-project.asciidoc
@@ -82,9 +82,7 @@ The further steps in the New Project Wizard depend on the selected deployment
 configuration; the steps listed in this section are for the default servlet
 configuration.
 ifdef::web[]
-See <<dummy/../../../framework/advanced/advanced-gae#advanced.gae,"Google App
-Engine Integration">> and <<dummy/../../../framework/portal/portal-overview.asciidoc#portal.overview,"Portal Integration">> for instructions regarding the use of Vaadin in the alternative
-environments.
+See <<dummy/../../../framework/portal/portal-overview.asciidoc#portal.overview,"Portal Integration">> for instructions regarding the use of Vaadin with portals.
 endif::web[]
 
 [guilabel]#Vaadin version#:: Select the Vaadin version to use. The drop-down list shows, by default, the