Add Qt for Windows support to Bazel build.

As a preparation to support Bazel for Windows build (#948), this makes
"qt_win" repository available for Bazel build on Windows.

There must be no observable behavior change in mac/Linux Bazel builds.

PiperOrigin-RevId: 645598529

src/WORKSPACE.bazel

@@ -189,6 +189,12 @@ qt_mac_repository(
   default_path = MACOS_QT_PATH,  # can be replaced with MOZC_QT_PATH envvar.
 )
 
+# Qt for Windows
+new_local_repository(
+    name = "qt_win",
+    build_file = "@//bazel:BUILD.qt_win.bazel",
+    path = "third_party/qt",
+)
 
 # Google Toolbox for Mac
 # https://github.com/google/google-toolbox-for-mac

src/bazel/BUILD.qt_win.bazel

@@ -0,0 +1,43 @@
+package(
+    default_visibility = ["//visibility:public"],
+)
+
+config_setting(
+    name = "debug_build",
+    values = {
+        "compilation_mode": "dbg",
+    },
+    visibility = ["//visibility:private"],
+)
+
+cc_library(
+    name = "qt_win",
+    srcs = select({
+        ":debug_build": [
+            "lib/Qt6Cored.lib",
+            "lib/Qt6Guid.lib",
+            "lib/Qt6Widgetsd.lib",
+        ],
+        "//conditions:default": [
+            "lib/Qt6Core.lib",
+            "lib/Qt6Gui.lib",
+            "lib/Qt6Widgets.lib",
+        ],
+    }),
+    hdrs = glob([
+        "include"
+    ]),
+    includes = [
+        "include",
+        "include/QtCore",
+        "include/QtGui",
+        "include/QtWidgets",
+    ],
+    target_compatible_with = ["@platforms//os:windows"],
+)
+
+exports_files([
+    "bin/moc.exe",
+    "bin/uic.exe",
+    "bin/rcc.exe",
+])

src/bazel/qt.bzl

@@ -50,6 +50,7 @@ def mozc_cc_qt_library(name, deps = [], **kwargs):
             default = ["//third_party/qt:qt_native"],
             oss_linux = ["@qt_linux//:qt_linux"],
             oss_macos = ["@qt_mac//:qt_mac"],
+            oss_windows = ["@qt_win//:qt_win"],
         ),
         **kwargs
     )
@@ -66,6 +67,7 @@ def mozc_cc_qt_binary(name, deps = [], **kwargs):
             default = ["//third_party/qt:qt_native"],
             oss_linux = ["@qt_linux//:qt_linux"],
             oss_macos = ["@qt_mac//:qt_mac"],
+            oss_windows = ["@qt_win//:qt_win"],
         ),
         **kwargs
     )
@@ -84,11 +86,13 @@ def mozc_qt_moc(name, srcs, outs):
             default = "$(location //third_party/qt:moc) -p $$(dirname $<) -o $@ $(SRCS)",
             oss_linux = "$(location @qt_linux//:libexec/moc) -p $$(dirname $<) -o $@ $(SRCS)",
             oss_macos = "$(location @qt_mac//:libexec/moc) -p $$(dirname $<) -o $@ $(SRCS)",
+            oss_windows = "$(location @qt_win//:bin/moc.exe) -p $$(dirname $<) -o $@ $(SRCS)",
         ),
         tools = mozc_select(
             default = ["//third_party/qt:moc"],
             oss_linux = ["@qt_linux//:libexec/moc"],
             oss_macos = ["@qt_mac//:libexec/moc"],
+            oss_windows = ["@qt_win//:bin/moc.exe"],
         ),
     )
 
@@ -101,11 +105,13 @@ def mozc_qt_uic(name, srcs, outs):
             default = "$(location //third_party/qt:uic) -o $@ $(SRCS)",
             oss_linux = "$(location @qt_linux//:libexec/uic) -o $@ $(SRCS)",
             oss_macos = "$(location @qt_mac//:libexec/uic) -o $@ $(SRCS)",
+            oss_windows = "$(location @qt_win//:bin/uic.exe) -o $@ $(SRCS)",
         ),
         tools = mozc_select(
             default = ["//third_party/qt:uic"],
             oss_linux = ["@qt_linux//:libexec/uic"],
             oss_macos = ["@qt_mac//:libexec/uic"],
+            oss_windows = ["@qt_win//:bin/uic.exe"],
         ),
     )
 
@@ -118,11 +124,13 @@ def mozc_qt_rcc(name, qrc_name, qrc_file, srcs, outs):
             default = "$(location //third_party/qt:rcc) -o $@ -name " + qrc_name + " " + qrc_file,
             oss_linux = "$(location @qt_linux//:libexec/rcc) -o $@ -name " + qrc_name + " $(location " + qrc_file + ")",
             oss_macos = "$(location @qt_mac//:libexec/rcc) -o $@ -name " + qrc_name + " $(location " + qrc_file + ")",
+            oss_windows = "$(location @qt_win//:bin/rcc.exe) -o $@ -name " + qrc_name + " $(location " + qrc_file + ")",
         ),
         tools = mozc_select(
             default = ["//third_party/qt:rcc"],
             oss_linux = ["@qt_linux//:libexec/rcc"],
             oss_macos = ["@qt_mac//:libexec/rcc"],
+            oss_windows = ["@qt_win//:bin/rcc.exe"],
         ),
     )