WIP: Migrate Wiki content over to src/docs

docs/ipc_fuzzer.md

+# Introduction
+
+A chromium IPC fuzzer is under development by aedla and tsepez. The fuzzer lives under `src/tools/ipc_fuzzer/` and is running on ClusterFuzz. A previous version of the fuzzer was a simple bitflipper, which caught around 10 bugs. A new version is doing smarter mutations and generational fuzzing. To do so, each `ParamTraits<Type>` needs a corresponding `FuzzTraits<Type>`. Feel free to contribute.
+
+
+---
+
+# Working with the fuzzer
+
+## Build instructions
+  * add `enable_ipc_fuzzer=1` to `GYP_DEFINES`
+  * build `ipc_fuzzer_all` target
+  * component builds are currently broken, sorry
+  * Debug builds are broken; only Release mode works.
+
+## Replaying ipcdumps
+  * `tools/ipc_fuzzer/scripts/play_testcase.py path/to/testcase.ipcdump`
+  * more help: `tools/ipc_fuzzer/scripts/play_testcase.py -h`
+
+## Listing messages in ipcdump
+  * `out/`_Build_`/ipc_message_util --dump path/to/testcase.ipcdump`
+
+## Updating fuzzers in ClusterFuzz
+  * `tools/ipc_fuzzer/scripts/cf_package_builder.py`
+  * upload `ipc_fuzzer_mut.zip` and `ipc_fuzzer_gen.zip` under build directory to ClusterFuzz
+
+## Contributing FuzzTraits
+  * add them to tools/ipc\_fuzzer/fuzzer/fuzzer.cc
+  * thanks!
+
+
+---
+
+# Components
+
+## ipcdump logger
+  * add `enable_ipc_fuzzer=1` to `GYP_DEFINES`
+  * build `chrome` and `ipc_message_dump` targets
+  * run chrome with `--no-sandbox --ipc-dump-directory=/path/to/ipcdump/directory`
+  * ipcdumps will be created in this directory for each renderer using the format _pid_.ipcdump
+
+## ipcdump replay
+Lives under `ipc_fuzzer/replay`. The renderer is replaced with `ipc_fuzzer_replay` using `--renderer-cmd-prefix`. This is done automatically with the `ipc_fuzzer/play_testcase.py` convenience script.
+
+## ipcdump mutator / generator
+Lives under `ipc_fuzzer/fuzzer`. This is the code that runs on ClusterFuzz. It uses `FuzzTraits<Type>` to mutate ipcdumps or generate them out of thin air.
+
+
+---
+
+# Problems, questions, suggestions
+Send them to mbarbella@chromium.org.