GWP-ASan: Enable on Android

Enable the GWP-ASan unit tests on Android and wire-in GWP-ASan in to the
crash handler and browser (for now it's still disabled by default and
not wired in to webview.)

Bug: 973167
Change-Id: I705bc3fcd4469c90099d91b9b2ae16f2a9c93fab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733567
Commit-Queue: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Auto-Submit: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Reviewed-by: Vitaly Buka <vitalybuka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#685385}

components/gwp_asan/BUILD.gn

@@ -14,7 +14,7 @@ test("gwp_asan_unittests") {
     "//components/gwp_asan/common:unit_tests",
     "//testing/gtest",
   ]
-  if (is_win || is_mac || is_linux) {
+  if (is_win || is_mac || is_linux || is_android) {
     deps += [
       "//components/gwp_asan/client:unit_tests",
       "//components/gwp_asan/crash_handler:unit_tests",

components/gwp_asan/buildflags/buildflags.gni

@@ -6,7 +6,9 @@ import("//base/allocator/allocator.gni")
 import("//build/config/allocator.gni")
 
 # Windows/x86 is disabled due to https://crbug.com/969146
-supported_platform = is_mac || (is_win && current_cpu == "x64")
+# Android component builds are disabled due to https://crbug.com/976399
+supported_platform = is_mac || (is_win && current_cpu == "x64") ||
+                     (is_android && !is_component_build)
 
 declare_args() {
   # Is GWP-ASan malloc/PartitionAlloc hooking enabled for chrome/ on a given