[libFuzzer][Windows] Improve docs

Fix link to reproduce tool.
Include note about using powershell.
Remove "> " from command.
Mention that document is for libFuzzer explicitly.
Be more consistent about capitalization of "libFuzzer".

TBR=mmoroz@chromium.org

Bug: 901836
Change-Id: I9a91be5d01c2707366b1d8100cb0823c221aa82e
Reviewed-on: https://chromium-review.googlesource.com/c/1318918
Commit-Queue: Jonathan Metzman <metzman@chromium.org>
Reviewed-by: Max Moroz <mmoroz@chromium.org>
Reviewed-by: Jonathan Metzman <metzman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605684}

testing/libfuzzer/README.md

@@ -62,8 +62,8 @@ libFuzzer.
 [Efficient Fuzzer Guide]: efficient_fuzzer.md
 [Guide to libprotobuf-mutator]: libprotobuf-mutator.md
 [ClusterFuzz Integration]: clusterfuzz.md
-[Reproducing]: https://github.com/google/clusterfuzz-tools
 [Reproducing on Windows]: reproducing_on_windows.md
+[Reproducing on Linux and Mac]: https://github.com/google/clusterfuzz-tools
 [Reference]: reference.md
 [ClusterFuzz Bugs]: https://bugs.chromium.org/p/chromium/issues/list?can=1&q=label:Stability-LibFuzzer%20label:ClusterFuzz&sort=-modified&colspec=ID%20Pri%20M%20Stars%20ReleaseBlock%20Component%20Status%20Owner%20Summary%20OS%20Modified
 [Pdfium Bugs]: https://bugs.chromium.org/p/pdfium/issues/list?can=1&q=libfuzzer&colspec=ID+Type+Status+Priority+Milestone+Owner+Summary&cells=tiles

testing/libfuzzer/reproducing_on_windows.md

-# Reproducing Crashes on Windows
+# Reproducing libFuzzer Crashes on Windows
 
 Since the [ClusterFuzz Reproduce Tool] does not work on Windows, you will need
 to reproduce crashes found by ClusterFuzz manually. Luckily, this process is
-usually very simple. Below are the steps (assuming use of cmd.exe):
+usually very simple. Below are the steps:
+
+*** note
+**Requirements:** These commands are intended to work in cmd.exe, not
+powershell.
+***
 
 1. Download the test case from ClusterFuzz (if you are CCed on an issue filed by
    ClusterFuzz, a link to it is next to "Reproducer testcase" in the
    bug description). For the rest of this walkthrough, we call the path of this
    file: `$TESTCASE_PATH`.
 
-2. Generate gn build configuration for fuzzers:
+2. Generate gn build configuration for libFuzzer:
 
 ```
-python tools\mb\mb.py gen -m chromium.fyi -b "Libfuzzer Upload Windows ASan" out\libfuzzer
+python tools\mb\mb.py gen -m chromium.fyi -b "Libfuzzer Upload Windows ASan" out\libFuzzer
 ```
 
 3. Build the fuzzer:
 
 ```
-autoninja -C .\out\libfuzzer\ $FUZZER_NAME
+autoninja -C .\out\libFuzzer\ $FUZZER_NAME
 ```
 
 4. Set the `ASAN_OPTIONS` environment variable to be the same as ClusterFuzz.
@@ -27,13 +32,13 @@ Here is an example value of `ASAN_OPTIONS` that is similar to its value on
 ClusterFuzz:
 
 ```
-> set ASAN_OPTIONS=redzone=256:print_summary=1:handle_sigill=1:strict_string_check=1:allocator_release_to_os_interval_ms=500:print_suppressions=0:strict_memcmp=1:allow_user_segv_handler=0:use_sigaltstack=1:handle_sigfpe=1:handle_sigbus=1:detect_stack_use_after_return=0:alloc_dealloc_mismatch=0:detect_leaks=0:print_scariness=1:allocator_may_return_null=1:handle_abort=1:check_malloc_usable_size=0:detect_container_overflow=0:quarantine_size_mb=256:detect_odr_violation=0:symbolize=1:handle_segv=1:fast_unwind_on_fatal=1
+set ASAN_OPTIONS=redzone=256:print_summary=1:handle_sigill=1:strict_string_check=1:allocator_release_to_os_interval_ms=500:print_suppressions=0:strict_memcmp=1:allow_user_segv_handler=0:use_sigaltstack=1:handle_sigfpe=1:handle_sigbus=1:detect_stack_use_after_return=0:alloc_dealloc_mismatch=0:detect_leaks=0:print_scariness=1:allocator_may_return_null=1:handle_abort=1:check_malloc_usable_size=0:detect_container_overflow=0:quarantine_size_mb=256:detect_odr_violation=0:symbolize=1:handle_segv=1:fast_unwind_on_fatal=1
 ```
 
 5. Run the fuzzer:
 
 ```
-.\out\libfuzzer\$FUZZER_NAME -runs=100 $TESTCASE_PATH
+.\out\libFuzzer\$FUZZER_NAME -runs=100 $TESTCASE_PATH
 ```
 
 Send an email to fuzzing@chromium.org if you run into any issues.