Remove all blimp client code.

blimp/client/README.md

-# Blimp Client
-
-This document contains documentation for the blimp client code organization.
-
-For a quick guide for how to add Java files to an existing directory, see
-[Adding Java files](#adding-java-files) below.
-
-[TOC]
-
-## Code Organization
-
-The blimp client has two main directories to be used for code, `core` and
-`public`. Embedders should only ever have to deal with the `public` directory.
-
-There are sub-directories resembling the ones in `core` for parts that needs to
-be exposed to embedders, such as `BlimpContents`.
-
-All Java-code is put in the `public/android` directory, with a package
-organization that resembles the one in `core`.
-
-Within `//blimp/client`, the `visibility` feature of GN is heavily used to
-ensure that embedders and dependencies are correctly set up. Currently, the
-`app` directory is not fully extracted out as an embedder, so it does sometime
-depend directly on code in `core`, but that should change when the migration to
-`core` is finished.
-
-### The core directory
-
-The `core` directory is to be used for all business logic code, and is an
-internal concept of the client code.
-
-There are sub-directories for logically separate parts, such as `contents` for
-code that relate to the contents of a web page. All Android code is put into
-their respective directories, so Android and Java-code related to `contents`
-is put in `contents/android`.
-
-Each of the sub-directories have their own `BUILD.gn` file, which includes
-targets for both C++ and Java.
-
-*   `//blimp/client/core/`
-    *   `compositor/` Code related to the Chrome Compositor.
-    *   `contents/` Code related to the contents of a web page.
-    *   `contents/android/` JNI bridges and Java-code for `contents`.
-    *   **`context/` Code related to the context (`BlimpClientContext`), which
-        is the core functionality used by all embedders.**
-    *   `context/android` JNI bridges and Java-code for `context`.
-    *   `session/` Code related to the session with the engine.
-
-Most code in `core` do not need any Java counterparts unless the embedder is
-written for Android and it is typically only needed for things that relate to
-the embedder UI.
-
-#### Actual and dummy implementations of core
-
-The `core` directory has two implementations of the public API, a dummy one
-and a real one. The default is to use the dummy API, but an embedder can choose
-to enable full blimp support by setting the GN arguments `enable_blimp_client`
-to `true`.
-
-Basically only the implementation of `BlimpClientContext` has been split out
-into two parts (both in C++ and Java), and the choice of which backing
-implementation to be used is selected by the `enable_blimp_client` flag. These
-two implementations live in `//blimp/client/context`.
-
-### The public directory
-
-The `public` directory represents the public API of the blimp client, to be
-used by the embedders.
-
-Embedders should be able to depend on `//blimp/client/public` for C++ code,
-and for Java they should depend on `//blimp/client/public:public_java`. This
-automatically pulls in the dependencies on the code in `core`.
-
-*   `//blimp/client/public/`
-    *   `android/` All Android-related code, including Java-code. This includes
-        also code from all the sub-directories such as `contents`.
-    *   `contents/` Code from `//blimp/client/core/contents/` that needs to be
-        exposed to embedders.
-    *   `session/` Code from `//blimp/client/core/session/` that needs to be
-        exposed to embedders.
-
-### Other directories
-
-#### The app directory
-
-The `app` directory represents the directory that contains embedder code for
-a Blimp application on its own. Under a transition period, this directory
-also contains code that depends directly on `core`, until everything can be
-updated to depend only on `public`.
-
-#### The feature directory
-
-The `feature` directory is from the old directory organization, and all the
-content of this will move over to the `core` directory. The feature-specific
-code will move together with the usage of the feature itself, such as
-`core/contents`.
-
-#### The session directory
-
-The `session` directory is from the old directory organization, and all the
-content of this will move over to the `core/session` directory.
-
-#### The support directory
-
-The `support` directory is a directory providing help to embedders. This
-typically includes a default implementation of an interface from
-`//blimp/client/public` or other helpful tools.
-
-#### The test directory
-
-The `test` directory contains tools helpful for testing client code.
-
-### Adding Java files {#adding-java-files}
-
-Most of Blimp is written in C++, but some parts have to be written in Java for
-the Android platform. For those parts of the code, it is required to add an
-`android` sub-directory, and put JNI-bridges and Java files within there.
-
-This will mostly happen in a sub-directory of `core`, so the following section
-explains how to add a Java file with JNI hooks for the imaginary sub-directory `//blimp/client/core/foo`. Conceptually, it's adding a Java-version of the C++
-class `Foo`, that lives in `//blimp/client/core/foo/foo.[cc|h]`.
-
-*   The file Foo.java should be added at:
-    `//blimp/client/core/foo/android/java/src/org/chromium/blimp/core/foo/Foo.java`
-
-*   The JNI-bridge should live in:
-    `//blimp/client/core/foo/android/foo_android.[cc|h]`
-
-*   Add the JNI-bridge JNI registration to:
-     `//blimp/client/core/context/android/blimp_jni_registrar.cc`
-
-*   Add this to the top of `//blimp/client/core/foo/BUILD.gn`:
-
-    ```python
-    if (is_android) {
-      import("//build/config/android/config.gni")
-      import("//build/config/android/rules.gni")
-    }
-    ```
-
-*   Add the following targets to `//blimp/client/core/foo/BUILD.gn`:
-
-    ```python
-    android_library("foo_java") {
-      visibility = [ "//blimp/client/*" ]
-
-      java_files = [
-        "android/java/src/org/chromium/blimp/core/foo/Foo.java",
-      ]
-
-      deps = [
-        ...
-      ]
-    }
-
-    generate_jni("jni_headers") {
-      visibility = [ ":*" ]
-
-      sources = [
-        "android/java/src/org/chromium/blimp/core/foo/Foo.java",
-      ]
-
-      jni_package = "blimp/client/core/foo"
-    }
-    ```
-
-*   Edit the target `//blimp/client/core/foo:foo` to add this Android-part:
-
-    ```python
-    source_set("foo") {
-
-      ...
-
-      if (is_android) {
-       sources += [
-         "android/foo.cc",
-         "android/foo.h",
-       ]
-
-       deps += [ ":jni_headers" ]
-      }
-    }
-    ```
-
-*   Add `//blimp/client/core/foo:foo_java` as a dependency in
-    `//blimp/client/core:core_java`.