Add and document sccache support for Windows

The two `cl.exe` flags that confused sccache on my setup, and resulted
in uncacheable calls are the following:

- `/Brepro`
- `/showIncludes:user`

This CL disables these options if `cc_wrapper` is set and documents that
`chrome_pgo_phase` must be disabled if sccache will be used.

These settings result in a high number of sccache cache hits and
significant speed-up when not using Goma:

```
Compile requests                  27222
Compile requests executed         27222
Cache hits                        27218
Cache hits (C/C++)                27218
Cache misses                          4
Cache misses (C/C++)                  4
```

For the record, this change has been tested on Windows 10 Pro 20H2,
sccache v0.2.15, and Visual Studio Community 2019 in an Electron.js
build environment.

R=thakis@chromium.org, tikuta@chromium.org

Bug: 1224369,787983
Change-Id: I8e2921aabca04598119743906ec6989ef43167ad
Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2989169
Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#897180}
4 files changed
tree: 72a64e3a7c12a767e9d476d96b85cf3dcd18f2cc
  1. .clang-format
  2. .clang-tidy
  3. .eslintrc.js
  4. .git-blame-ignore-revs
  5. .gitattributes
  6. .gitignore
  7. .gn
  8. .mailmap
  9. .vpython
  10. .vpython3
  11. .yapfignore
  12. AUTHORS
  13. BUILD.gn
  14. CODE_OF_CONDUCT.md
  15. DEPS
  16. DIR_METADATA
  17. ENG_REVIEW_OWNERS
  18. LICENSE
  19. LICENSE.chromium_os
  20. OWNERS
  21. PRESUBMIT.py
  22. PRESUBMIT_test.py
  23. PRESUBMIT_test_mocks.py
  24. README.md
  25. WATCHLISTS
  26. android_webview/
  27. apps/
  28. ash/
  29. base/
  30. build/
  31. build_overrides/
  32. buildtools/
  33. cc/
  34. chrome/
  35. chromecast/
  36. chromeos/
  37. cloud_print/
  38. codelabs/
  39. codereview.settings
  40. components/
  41. content/
  42. courgette/
  43. crypto/
  44. dbus/
  45. device/
  46. docs/
  47. extensions/
  48. fuchsia/
  49. gin/
  50. google_apis/
  51. google_update/
  52. gpu/
  53. headless/
  54. infra/
  55. ios/
  56. ipc/
  57. jingle/
  58. media/
  59. mojo/
  60. native_client_sdk/
  61. net/
  62. pdf/
  63. ppapi/
  64. printing/
  65. remoting/
  66. rlz/
  67. sandbox/
  68. services/
  69. skia/
  70. sql/
  71. storage/
  72. styleguide/
  73. testing/
  74. third_party/
  75. tools/
  76. ui/
  77. url/
  78. weblayer/
README.md

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Documentation in the source is rooted in docs/README.md.

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