Add Android fonts to blimp engine

The blimp engine is currently using Linux fonts, which works well
for Linux clients. However, for Android clients, Skia should be
instructed to use Android fonts instead to ensure that the font
rendering works correctly.

This CL adds a starting set of fonts to be used, ensures that they
are part of the engine bundle, and provides documentation for how
to use them in locally hosted engines and also for how to keep the
fonts up to date.

This also updates the engine manifest and starts loading a new
dynamic library while running the engine plus fixes the documentation
for running the engine as a container.

Initial CL: https://codereview.chromium.org/1735783002/
Revert: https://codereview.chromium.org/1772343003/

BUG=585668, 588929

Review URL: https://codereview.chromium.org/1776133002

Cr-Commit-Position: refs/heads/master@{#380022}

3 files changed, 41 insertions, 3 deletions

diff --git a/blimp/docs/container.md b/blimp/docs/container.md
index 31adc80..6cec582 100644
--- a/blimp/docs/container.md
+++ b/blimp/docs/container.md
@@ -56,7 +56,7 @@ dependencies.
 Using the tarfile you can create a Docker image:
 
 ```bash
-docker build -t blimp_engine - < ./out-linux/Debug/blimp_engine_bundle.tar
+docker build -t blimp_engine - < ./out-linux/Debug/blimp_engine_bundle.tar.gz
 ```
 
 ## Running the Engine in a Docker Container
@@ -74,7 +74,8 @@ few files that are not provided by the container. You need:
     public certificate. Permissions should be set to 644.
 *   `$CONFIG_DIR/client_token`: A file with a non-empty string used as the
     client token (the shared secret between the client and the engine).
-    Persmissions should also be set to 644.
+    Permissions should also be set to 644. See [running](running.md) for how
+    to get the default token from the source code.
 
 This setup step is only required once and can be reused for all the rest of the
 runs of the engine.
@@ -94,4 +95,3 @@ docker run ... blimp_engine --with-my-flags
 ```
 See the [blimp engine `Dockerfile`](../engine/Dockerfile) to find out what flags
 are passed by default.
-
diff --git a/blimp/docs/fonts.md b/blimp/docs/fonts.md
new file mode 100644
index 0000000..379a5df
--- /dev/null
+++ b/blimp/docs/fonts.md
@@ -0,0 +1,35 @@
+# Updating Blimp Fonts
+
+1.  Clone the git-repositories listed in
+    `//third_party/blimp_fonts/README.chromium`, and roll forward to the commit
+    you want.
+1.  Copy the necessary files to `//third_party/blimp_fonts/font_bundle`.
+1.  Verify that the `fonts.xml` file include the correct fonts.
+1.  Verify that the `LICENSE` file is still up to date and lists all relevant
+    licenses and which fonts use which license.
+1.  Update the `//third_party/blimp_fonts` target to include all the
+    current fonts and their license files.
+1.  Update the engine dependencies using
+    `//blimp/tools/generate-engine-manifest.py`. This step is documented in
+    `//blimp/docs/container.md`.
+1.  Run the `upload_to_google_storage.py` (from depot_tools) script to upload
+    the files. You must do this in the `//third_party/blimp_fonts` directory.
+    To do this, execute:
+
+    ```bash
+    upload_to_google_storage.py --archive -b chromium-fonts font_bundle
+    ```
+
+1.  Add all the `font_bundle.tar.gz.sha1` file to the chromium src repository,
+    by executing the following command:
+
+    ```bash
+    git add ./third_party/blimp_fonts/font_bundle.tar.gz.sha1
+    ```
+
+1.  Commit and upload the change for review:
+
+    ```bash
+    git commit
+    git cl upload
+    ```
diff --git a/blimp/docs/running.md b/blimp/docs/running.md
index 8accd3e..bb92199 100644
--- a/blimp/docs/running.md
+++ b/blimp/docs/running.md
@@ -100,6 +100,8 @@ also start a new shell and keep the following command running:
   compositor.
 * `--disable-cached-picture-raster`: Ensures that rasterized content is not
   destroyed before serialization.
+* `--android-fonts-path=$PATH`: Path to where the fonts are located.
+  Typically this would be `out-linux/Debug/gen/third_party/blimp_fonts`.
 
 #### Typical invocation
 When the client connects to a manually specified engine instead of using the
@@ -122,6 +124,7 @@ out-linux/Debug/blimp_engine_app \
   --disable-cached-picture-raster \
   --blimp-client-token-path=/tmp/blimpengine-token \
   --user-data-dir=/tmp/blimpengine \
+  --android-fonts-path=out-linux/Debug/gen/third_party/blimp_fonts \
   --enable-logging=stderr \
   --vmodule="blimp*=1"
 ```