[bzlmod] Support repo @google_cloud_cpp in bzlmod (#41311)

This change should enable us to build most C/C++ tests with bzlmod.

`googleapis` is also updated because google_cloud_cpp 2.35.0 uses a modified version of googleapis. This requires us to copy some boilerplate code from upstream (BCR and google_cloud_cpp respectively).

Alternatively we could also use google_cloud_cpp from BCR, it takes less coding work but the lowest version available is 3.0.0 and requires a bunch of version bumps to other modules, so it might be more risky.

`rules_proto` version is increase to 7.1.0 (requested by google_cloud_cpp)

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Closes #41311

PiperOrigin-RevId: 859764899

MODULE.bazel

@@ -28,7 +28,6 @@ bazel_dep(name = "bazel_skylib", version = "1.8.1")
 bazel_dep(name = "boringssl", version = "0.20241024.0")  # mistmatched 20241211
 bazel_dep(name = "c-ares", version = "1.19.1", repo_name = "com_github_cares_cares")
 bazel_dep(name = "envoy_api", version = "0.0.0-20251216-6ef568c")
-bazel_dep(name = "googleapis", version = "0.0.0-20251003-2193a2bf", repo_name = "com_google_googleapis")
 bazel_dep(name = "googleapis-cc", version = "1.0.0")
 bazel_dep(name = "googleapis-grpc-cc", version = "1.0.0")
 bazel_dep(name = "googleapis-python", version = "1.0.0")
@@ -105,3 +104,25 @@ include("//bazel:com_google_fuzztest.MODULE.bazel")
 
 # Provides repo @grpc_custom_exec_properties.
 include("//bazel:grpc_custom_exec_properties.MODULE.bazel")
+
+# -- google_cloud_cpp 2.35.0 related repos, which requires a modified version of googleapis, hence the version pinning.
+bazel_dep(name = "googleapis", version = "0.0.0-20251003-2193a2bf", repo_name = "com_google_googleapis")
+single_version_override(
+    module_name = "googleapis",
+    patch_strip = 1,
+    patches = [
+        "//bazel:googleapis/patches/fix_google_cloud_cpp.patch",
+    ],
+    version = "0.0.0-20251003-2193a2bf",
+)
+
+bazel_dep(name = "google_cloud_cpp", version = "2.35.0", dev_dependency = True)
+archive_override(
+    module_name = "google_cloud_cpp",
+    integrity = "sha256-geooz55bsDLTVrAYdAnzCxA1+OpbUwZ16iSMimwAcKo=",
+    strip_prefix = "google-cloud-cpp-2.35.0",
+    urls = [
+        "https://storage.googleapis.com/grpc-bazel-mirror/github.com/googleapis/google-cloud-cpp/archive/refs/tags/v2.35.0.tar.gz",
+        "https://github.com/googleapis/google-cloud-cpp/archive/refs/tags/v2.35.0.tar.gz",
+    ],
+)

bazel/googleapis/patches/fix_google_cloud_cpp.patch

@@ -0,0 +1,25 @@
+# Inspired by https://github.com/googleapis/google-cloud-cpp/blob/2839e9dba793ca023e11ea67f201f66f74fa7d3e/bazel/googleapis.BUILD
+diff --git a/BUILD.bazel b/BUILD.bazel
+index 026553f5c..7c7bc0419 100644
+--- a/BUILD.bazel
++++ b/BUILD.bazel
+@@ -1,3 +1,19 @@
++package(default_visibility = ["//visibility:public"])
++
++licenses(["notice"])  # Apache 2.0
++
++# This build file overlays on top of the BUILD files for the googleapis repo,
++# and it adds a target that lets us include their header files using
++# angle-brackets, thus treating their headers as system includes. This allows
++# us to dial-up the warnings in our own code, without seeing compiler warnings
++# from their headers, which we do not own.
++cc_library(
++    name = "googleapis_system_includes",
++    includes = [
++        ".",
++    ],
++)
++
+ genrule(
+     name = "build_gen",
+     srcs = glob(

templates/MODULE.bazel.inja

@@ -28,7 +28,6 @@ bazel_dep(name = "bazel_skylib", version = "1.8.1")
 bazel_dep(name = "boringssl", version = "0.20241024.0")  # mistmatched 20241211
 bazel_dep(name = "c-ares", version = "1.19.1", repo_name = "com_github_cares_cares")
 bazel_dep(name = "envoy_api", version = "0.0.0-20251216-6ef568c")
-bazel_dep(name = "googleapis", version = "0.0.0-20251003-2193a2bf", repo_name = "com_google_googleapis")
 bazel_dep(name = "googleapis-cc", version = "1.0.0")
 bazel_dep(name = "googleapis-grpc-cc", version = "1.0.0")
 bazel_dep(name = "googleapis-python", version = "1.0.0")
@@ -105,3 +104,25 @@ include("//bazel:com_google_fuzztest.MODULE.bazel")
 
 # Provides repo @grpc_custom_exec_properties.
 include("//bazel:grpc_custom_exec_properties.MODULE.bazel")
+
+# -- google_cloud_cpp 2.35.0 related repos, which requires a modified version of googleapis, hence the version pinning.
+bazel_dep(name = "googleapis", version = "0.0.0-20251003-2193a2bf", repo_name = "com_google_googleapis")
+single_version_override(
+    module_name = "googleapis",
+    patch_strip = 1,
+    patches = [
+        "//bazel:googleapis/patches/fix_google_cloud_cpp.patch",
+    ],
+    version = "0.0.0-20251003-2193a2bf",
+)
+
+bazel_dep(name = "google_cloud_cpp", version = "2.35.0", dev_dependency = True)
+archive_override(
+    module_name = "google_cloud_cpp",
+    integrity = "sha256-geooz55bsDLTVrAYdAnzCxA1+OpbUwZ16iSMimwAcKo=",
+    strip_prefix = "google-cloud-cpp-2.35.0",
+    urls = [
+        "https://storage.googleapis.com/grpc-bazel-mirror/github.com/googleapis/google-cloud-cpp/archive/refs/tags/v2.35.0.tar.gz",
+        "https://github.com/googleapis/google-cloud-cpp/archive/refs/tags/v2.35.0.tar.gz",
+    ],
+)

tools/bazelify_tests/test/bazel_build_with_bzlmod_linux.sh

@@ -20,16 +20,14 @@ tools/bazel \
     --bazelrc=tools/remote_build/linux_bzlmod.bazelrc \
     build \
     -- \
-    :all \
-    -:grpcpp_csm_observability  # Needs google_cloud_cpp to be added to BCR
+    :all
 
 # Test if examples are buildable without dev dependencies.
 tools/bazel \
     --bazelrc=tools/remote_build/linux_bzlmod.bazelrc \
     build \
     -- \
-    //examples/cpp/... \
-    -//examples/cpp/csm/...  # Needs grpcpp_csm_observability
+    //examples/cpp/...
 
 # Test if a few basic tests can pass.
 # This is a temporary sanity check covering essential features,
@@ -64,5 +62,4 @@ tools/bazel \
     build \
     --define=//third_party:grpc_use_openssl=true \
     -- \
-    :all \
-    -:grpcpp_csm_observability  # Needs google_cloud_cpp to be added to BCR
+    :all

tools/remote_build/linux_bzlmod.bazelrc

@@ -22,6 +22,6 @@ common --enable_workspace=false
 # TODO(weizheyuan): Re-enable this check once we upgrade all of the
 # transitive dependencies that are currently at mismatched versions.
 #common --check_direct_dependencies=error
-common --ignore_dev_dependency
+common --ignore_dev_dependency=false
 
 build --jobs=200