Upgrade IWYU to use clang 13 (#28891)

* Upgrade IWYU to use clang 13

* Update by review

templates/tools/dockerfile/grpc_iwyu/Dockerfile.template

@@ -14,17 +14,17 @@
   # See the License for the specific language governing permissions and
   # limitations under the License.
   
-  FROM debian:11
-  
-  RUN apt-get update && apt-get install -y clang-11 llvm-11-dev libclang-11-dev clang-format-11 jq git cmake python
-  
-  ENV CLANG_FORMAT=clang-format-11
+  FROM silkeh/clang:13
 
+  # Install prerequisites for the iwyu script
+  RUN apt-get update && apt-get install -y python3 jq git cmake python zlib1g-dev libtinfo-dev && apt-get clean
+  
+  # Install IWYU for Clang 13
   RUN git clone https://github.com/include-what-you-use/include-what-you-use.git /iwyu
-  # latest commit on the clang 11 branch
-  RUN cd /iwyu && git checkout 5db414ac448004fe019871c977905cb7c2cff23f
-
-  RUN mkdir /iwyu_build && cd /iwyu_build && cmake -G "Unix Makefiles" -DCMAKE_PREFIX_PATH=/usr/lib/llvm-11 /iwyu && make
+  RUN cd /iwyu && git checkout fbd921d6640bf1b18fe5a8a895636215367eb6b9
+  RUN mkdir /iwyu_build && cd /iwyu_build ${'\\'}
+      && cmake -G "Unix Makefiles" /iwyu ${'\\'}
+      && make
 
   ADD iwyu.sh /
   

tools/dockerfile/grpc_iwyu/Dockerfile

@@ -12,17 +12,17 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM debian:11
+FROM silkeh/clang:13
 
-RUN apt-get update && apt-get install -y clang-11 llvm-11-dev libclang-11-dev clang-format-11 jq git cmake python
-
-ENV CLANG_FORMAT=clang-format-11
+# Install prerequisites for the iwyu script
+RUN apt-get update && apt-get install -y python3 jq git cmake python zlib1g-dev libtinfo-dev && apt-get clean
 
+# Install IWYU for Clang 13
 RUN git clone https://github.com/include-what-you-use/include-what-you-use.git /iwyu
-# latest commit on the clang 11 branch
-RUN cd /iwyu && git checkout 5db414ac448004fe019871c977905cb7c2cff23f
-
-RUN mkdir /iwyu_build && cd /iwyu_build && cmake -G "Unix Makefiles" -DCMAKE_PREFIX_PATH=/usr/lib/llvm-11 /iwyu && make
+RUN cd /iwyu && git checkout fbd921d6640bf1b18fe5a8a895636215367eb6b9
+RUN mkdir /iwyu_build && cd /iwyu_build \
+    && cmake -G "Unix Makefiles" /iwyu \
+    && make
 
 ADD iwyu.sh /
 

tools/dockerfile/grpc_iwyu/iwyu.sh

@@ -37,7 +37,7 @@ xargs -a iwyu_files.txt /iwyu/iwyu_tool.py -p compile_commands_for_iwyu.json -j
 /iwyu/fix_includes.py --nocomments < iwyu.out || true
 
 # reformat sources, since iwyu gets this wrong
-xargs -a iwyu_files.txt $CLANG_FORMAT -i
+xargs -a iwyu_files.txt ${CLANG_FORMAT:-clang-format} -i
 
 # TODO(ctiller): expand this to match the clang-tidy directories:
 #  | grep -E "(^include/|^src/core/|^src/cpp/|^test/core/|^test/cpp/)"