Fix jacoco-toolchain dependency.

Bazel 0.26 added the `jacocorunner` attribute on `java_toolchain`. Java targets now fail when using the new host java_toolchain because of a dependency cycle:

```
@bazel_tools//tools/jdk:JacocoCoverageRunner
@bazel_tools//tools/jdk:current_java_toolchain
@bazel_tools//tools/jdk:legacy_current_java_toolchain
@bazel_tools//tools/jdk:remote_toolchain
@remote_java_tools_linux//:toolchain
.-> @remote_java_tools_linux//:jacoco_coverage_runner (host)
|   @bazel_tools//tools/jdk:current_java_toolchain (host)
|   @bazel_tools//tools/jdk:legacy_current_java_toolchain (host)
|   @bazel_tools//tools/jdk:remote_toolchain (host)
|   @remote_java_tools_linux//:toolchain (host)
`-- @remote_java_tools_linux//:jacoco_coverage_runner (host)
```

The dependency is happening because `jacocorunner` in `java_toolchain` was declared as a `java_import` which depends on the host `java_toolchain`. The issue was not caught because we only run the java integration tests with `--java_toolchain` built at head. If we had run the tests also with `--host_java_toolchain` the issue would have been caught (see #8530).

This PR does the following:
* Makes `jacocorunner` attribute a `filegroup` instead of a `java_import` to avoid the dependency cycle.
* Converts the type of `jacocoRunner` in `JavaToolchain` from a `TransitiveInfoCollection` to `FilesToRunProvider` to be able to retrieve the executable jar from the `filegroup`.
* Adds testing with `--host_java_toolchain` of the java_tools built as head

This is a blocker for the new java_tools release (bazelbuild/java_tools#8).

Closes #8529.

PiperOrigin-RevId: 250876908

src/main/java/com/google/devtools/build/lib/rules/java/JavaCompilationHelper.java

@@ -269,13 +269,17 @@ public ImmutableList<Artifact> getBootclasspathOrDefault() {
   }
 
   public boolean addCoverageSupport() {
-    TransitiveInfoCollection jacocoRunner = javaToolchain.getJacocoRunner();
-    if (jacocoRunner != null
-        && JavaInfo.getProvider(JavaCompilationArgsProvider.class, jacocoRunner) != null) {
-      addLibrariesToAttributes(ImmutableList.of(jacocoRunner));
-      return true;
+    FilesToRunProvider jacocoRunner = javaToolchain.getJacocoRunner();
+    if (jacocoRunner == null) {
+      return false;
+    }
+    Artifact jacocoRunnerJar = jacocoRunner.getExecutable();
+    if (isStrict()) {
+      attributes.addDirectJar(jacocoRunnerJar);
     }
-    return false;
+    attributes.addCompileTimeClassPathEntry(jacocoRunnerJar);
+    attributes.addRuntimeClassPathEntry(jacocoRunnerJar);
+    return true;
   }
 
   /**

src/main/java/com/google/devtools/build/lib/rules/java/JavaTargetAttributes.java

@@ -158,6 +158,12 @@ public Builder addRuntimeClassPathEntries(NestedSet<Artifact> classPathEntries)
       return this;
     }
 
+    public Builder addCompileTimeClassPathEntry(Artifact entry) {
+      Preconditions.checkArgument(!built);
+      compileTimeClassPath.add(entry);
+      return this;
+    }
+
     public Builder addCompileTimeClassPathEntries(NestedSet<Artifact> entries) {
       Preconditions.checkArgument(!built);
       compileTimeClassPath.addTransitive(entries);
@@ -233,6 +239,12 @@ public Builder addDirectJars(NestedSet<Artifact> directJars) {
       return this;
     }
 
+    public Builder addDirectJar(Artifact directJar) {
+      Preconditions.checkArgument(!built);
+      this.directJars.add(directJar);
+      return this;
+    }
+
     public Builder addCompileTimeDependencyArtifacts(NestedSet<Artifact> dependencyArtifacts) {
       Preconditions.checkArgument(!built);
       compileTimeDependencyArtifacts.addTransitive(dependencyArtifacts);

src/main/java/com/google/devtools/build/lib/rules/java/JavaToolchain.java

@@ -106,7 +106,8 @@ public ConfiguredTarget create(RuleContext ruleContext)
             ruleContext.getPrerequisites(
                 "package_configuration", Mode.HOST, JavaPackageConfigurationProvider.class));
 
-    TransitiveInfoCollection jacocoRunner = ruleContext.getPrerequisite("jacocorunner", Mode.HOST);
+    FilesToRunProvider jacocoRunner =
+        ruleContext.getExecutablePrerequisite("jacocorunner", Mode.HOST);
 
     JavaToolchainProvider provider =
         JavaToolchainProvider.create(

src/main/java/com/google/devtools/build/lib/rules/java/JavaToolchainProvider.java

@@ -91,7 +91,7 @@ public static JavaToolchainProvider create(
       FilesToRunProvider ijar,
       ImmutableListMultimap<String, String> compatibleJavacOptions,
       ImmutableList<JavaPackageConfigurationProvider> packageConfiguration,
-      TransitiveInfoCollection jacocoRunner,
+      FilesToRunProvider jacocoRunner,
       JavaSemantics javaSemantics) {
     return new JavaToolchainProvider(
         label,
@@ -142,7 +142,7 @@ public static JavaToolchainProvider create(
   private final ImmutableList<String> javabuilderJvmOptions;
   private final boolean javacSupportsWorkers;
   private final ImmutableList<JavaPackageConfigurationProvider> packageConfiguration;
-  private final TransitiveInfoCollection jacocoRunner;
+  private final FilesToRunProvider jacocoRunner;
   private final JavaSemantics javaSemantics;
 
   @VisibleForSerialization
@@ -169,7 +169,7 @@ public static JavaToolchainProvider create(
       ImmutableList<String> javabuilderJvmOptions,
       boolean javacSupportsWorkers,
       ImmutableList<JavaPackageConfigurationProvider> packageConfiguration,
-      TransitiveInfoCollection jacocoRunner,
+      FilesToRunProvider jacocoRunner,
       JavaSemantics javaSemantics) {
     super(ImmutableMap.of(), Location.BUILTIN);
 
@@ -339,7 +339,7 @@ public ImmutableList<JavaPackageConfigurationProvider> packageConfiguration() {
     return packageConfiguration;
   }
 
-  public TransitiveInfoCollection getJacocoRunner() {
+  public FilesToRunProvider getJacocoRunner() {
     return jacocoRunner;
   }
 

src/test/shell/bazel/bazel_coverage_java_test.sh

@@ -23,6 +23,7 @@ source "${CURRENT_DIR}/../integration_test_setup.sh" \
 
 JAVA_TOOLCHAIN="$1"; shift
 add_to_bazelrc "build --java_toolchain=${JAVA_TOOLCHAIN}"
+add_to_bazelrc "build --host_java_toolchain=${JAVA_TOOLCHAIN}"
 
 JAVA_TOOLS_ZIP="$1"; shift
 if [[ "${JAVA_TOOLS_ZIP}" != "released" ]]; then
@@ -37,6 +38,7 @@ JAVA_TOOLS_ZIP_FILE_URL=${JAVA_TOOLS_ZIP_FILE_URL:-}
 if [[ $# -gt 0 ]]; then
     JAVABASE_VALUE="$1"; shift
     add_to_bazelrc "build --javabase=${JAVABASE_VALUE}"
+    add_to_bazelrc "build --host_javabase=${JAVABASE_VALUE}"
 fi
 
 function set_up() {

src/test/shell/bazel/bazel_java_test.sh

@@ -57,6 +57,7 @@ fi
 
 JAVA_TOOLCHAIN="$1"; shift
 add_to_bazelrc "build --java_toolchain=${JAVA_TOOLCHAIN}"
+add_to_bazelrc "build --host_java_toolchain=${JAVA_TOOLCHAIN}"
 
 JAVA_TOOLS_ZIP="$1"; shift
 if [[ "${JAVA_TOOLS_ZIP}" != "released" ]]; then
@@ -73,6 +74,7 @@ JAVA_TOOLS_ZIP_FILE_URL=${JAVA_TOOLS_ZIP_FILE_URL:-}
 if [[ $# -gt 0 ]]; then
     JAVABASE_VALUE="$1"; shift
     add_to_bazelrc "build --javabase=${JAVABASE_VALUE}"
+    add_to_bazelrc "build --host_javabase=${JAVABASE_VALUE}"
 fi
 
 function set_up() {

tools/jdk/BUILD.java_tools

@@ -59,7 +59,7 @@ java_toolchain(
         ":java_compiler_jar",
         ":jdk_compiler_jar",
     ],
-    jacocorunner = ":jacoco_coverage_runner"
+    jacocorunner = ":jacoco_coverage_runner_filegroup"
 )
 
 filegroup(
@@ -72,6 +72,11 @@ filegroup(
     srcs = ["java_tools/GenClass_deploy.jar"],
 )
 
+filegroup(
+    name = "jacoco_coverage_runner_filegroup",
+    srcs = ["java_tools/JacocoCoverage_jarjar_deploy.jar"],
+)
+
 java_import(
     name = "jacoco_coverage_runner",
     jars = ["java_tools/JacocoCoverage_jarjar_deploy.jar"],