Update Accessibility docs.

NOTRY=true

Change-Id: Idb932de14ca3eb79a1be1b175f19db48bf51fc07
Reviewed-on: https://chromium-review.googlesource.com/685413
Commit-Queue: Katie Dektar <katydek@google.com>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504694}

docs/accessibility/overview.md

@@ -195,7 +195,26 @@ function to retrieve the text properties (font family, font size,
 weight, etc.) at a specific character position.
 
 Parameterized attributes are particularly tricky to implement because
-of Chromium's multi-process architecture. More on this in the next section.
+of Chromium's multi-process architecture. More on this below.
+
+### Tools for inspecting the Accessibility tree
+
+Developers can inspect the accessibility tree in several ways:
+
+* By navigating to [chrome://accessibility/](chrome://accessibility)
+and inspecting a tree directly. Note that you may want to enable the
+'Internal' option. Click 'show accessibility tree' for a particular tab,
+then click again to refresh that tree.
+* Using the [https://developer.chrome.com/extensions/automation](
+Automation API).
+* Installing the [https://github.com/google/automation-inspector](
+Automation Inspector Chrome extension).
+* Or by using native tools:
+
+  - Android: UIAutomatorViewer
+  - macOS: Accessibility Inspector
+  - Windows: Inspect, AViewer, accProbe (and many others)
+
 
 ## Chromium's multi-process architecture
 

docs/accessibility/tests.md

@@ -107,6 +107,13 @@ ninja -C out/release chromevox_tests
 out/release/chromevox_tests --test-launcher-jobs=10
 ```
 
+### Select-To-Speak tests
+
+```
+ninja -C out/release unit_tests
+out/release/unit_tests --gtest_filter="*SelectToSpeak*"
+```
+
 ## Other locations of accessibility tests:
 
 Even this isn't a complete list. The tests described above cover more
@@ -121,3 +128,14 @@ ui/chromeos
 ui/views/accessibility
 ```
 
+## Helpful flags:
+
+Across all tests there are some helpful flags that will make testing easier.
+
+```
+--test-launcher-jobs=10  # This will run stuff in parallel and make flakes more obvious
+```
+
+```
+--gtest_filter="*Cats*"  # Filter which tests run. Takes a wildcard (*) optionally.
+```