Add Windows 20H2/1909/19042 support in base::win::Version.

BUG=1140170

Change-Id: Ia48e945f7b0c16d76daa28a12bf63afd646d2224
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2485149Reviewed-by: Robert Liao <robliao@chromium.org>
Commit-Queue: Robert Liao <robliao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#819968}

base/win/windows_version.cc

@@ -256,6 +256,8 @@ OSInfo::WOW64Status OSInfo::GetWOW64StatusForProcess(HANDLE process_handle) {
 // static
 Version OSInfo::MajorMinorBuildToVersion(int major, int minor, int build) {
   if (major == 10) {
+    if (build >= 19042)
+      return Version::WIN10_20H2;
     if (build >= 19041)
       return Version::WIN10_20H1;
     if (build >= 18363)

base/win/windows_version.h

@@ -49,6 +49,7 @@ enum class Version {
   WIN10_19H1 = 14,  // 19H1: Version 1903, Build 18362.
   WIN10_19H2 = 15,  // 19H2: Version 1909, Build 18363.
   WIN10_20H1 = 16,  // 20H1: Version 2004, Build 19041.
+  WIN10_20H2 = 17,  // 20H2: Version 2009, Build 19042.
   WIN_LAST,         // Indicates error condition.
 };
 

base/win/windows_version_unittest.cc

@@ -24,7 +24,9 @@ TEST(WindowsVersion, GetVersionExAndKernelOsVersionMatch) {
 
 TEST(OSInfo, MajorMinorBuildToVersion) {
   EXPECT_EQ(OSInfo::MajorMinorBuildToVersion(10, 0, 32767),
-            Version::WIN10_20H1);
+            Version::WIN10_20H2);
+  EXPECT_EQ(OSInfo::MajorMinorBuildToVersion(10, 0, 19042),
+            Version::WIN10_20H2);
   EXPECT_EQ(OSInfo::MajorMinorBuildToVersion(10, 0, 19041),
             Version::WIN10_20H1);
   EXPECT_EQ(OSInfo::MajorMinorBuildToVersion(10, 0, 18363),