isolates refactor: this change introduces 'dart:isolate' as a library. This is a

compiler/dartc.xml

 <project default="dist">
   <import file="sources.xml"/>
   <import file="test_sources.xml"/>
   <import file="corelib_sources.xml"/>
   <import file="compiler_corelib_sources.xml"/>
   <import file="domlib_sources.xml"/>
   <import file="htmllib_sources.xml"/>
   <import file="jsonlib_sources.xml"/>
+  <import file="isolatelib_sources.xml"/>
 
   <!--
     The file build.properties does not exist. If provided, properties can be customized.
   -->
   <property file="build.properties" />
 
   <!--
     Configuration properties.
   -->
   <property name="build.dir" value="out"/>
 
   <property name="build.classes.dir" value="${build.dir}/classes"/>
 
   <property name="corelib.source.dir" value="${build.dir}/corelib"/>
 
   <property name="domlib.source.dir" value="${build.dir}/../client/dom/"/>
 
   <property name="htmllib.source.dir" value="${build.dir}/../client/html/"/>
 
   <property name="jsonlib.source.dir" value="${build.dir}/../lib/json/"/>
 
+  <property name="isolatelib.source.dir" value="${build.dir}/../lib/isolate/"/>
+
   <property name="build.test.classes.dir" value="${build.dir}/test/classes"/>
 
   <property name="dartc.jar" value="${build.dir}/dartc.jar"/>
 
   <property name="corelib.jar" value="${build.dir}/corelib.jar"/>
 
   <property name="domlib.jar" value="${build.dir}/domlib.jar"/>
 
   <property name="htmllib.jar" value="${build.dir}/htmllib.jar"/>
 
   <property name="jsonlib.jar" value="${build.dir}/jsonlib.jar"/>
 
+  <property name="isolatelib.jar" value="${build.dir}/isolatelib.jar"/>
+
   <property name="dist.dir" value="${build.dir}/dist"/>
 
   <property name="test.report.dir" value="${build.dir}/test"/>
 
   <property name="third_party.dir" value="../third_party"/>
 
   <property name="d8" value="$DARTC_HOME/bin/d8.$OS"/>
 
   <property name="test_py" location="../tools/test.py"/>
 
@@ skipping 91 matching lines @@
     <delete dir="${build.dir}/api/dart/json"/>
     <delete file="${jsonlib.jar}"/>
     <mkdir dir="${jsonlib.source.dir}"/>
     <copy todir="${jsonlib.source.dir}/json">
       <filelist refid="jsonlib_resources"/>
     </copy>
     <jar destfile="${jsonlib.jar}" basedir="${jsonlib.source.dir}"/>
     <touch file="${build.dir}/jsonlib.jar.stamp"/>
   </target>
 
+  <target name="isolatelib.jar" description="Packages the isolate library resources into one jar file." >
+    <delete dir="${build.dir}/api/dart/isolate"/>
+    <delete file="${isolatelib.jar}"/>
+    <mkdir dir="${isolatelib.source.dir}"/>
+    <copy todir="${isolatelib.source.dir}/isolate">
+      <filelist refid="isolatelib_resources"/>
+    </copy>
+    <jar destfile="${isolatelib.jar}" basedir="${isolatelib.source.dir}"/>
+    <touch file="${build.dir}/isolatelib.jar.stamp"/>
+  </target>
+
+
   <target name="compile-tests" depends="compile" description="Compiles all of the java tests and copies the resources to the test classes directory." >
     <mkdir dir="${build.test.classes.dir}"/>
     <javac destdir="${build.test.classes.dir}"
            sourcepath=""
            srcdir="javatests"
            includes="${javatests_sources}"
            excludes="com/google/dart/compiler/vm/**"
            fork="true"
            debug="true">
       <classpath refid="classpath.compile.tests"/>
     </javac>
     <!--
       Copy the non-java resources.
     -->
     <copy todir="${build.test.classes.dir}">
       <filelist refid="javatests_resources"/>
     </copy>
   </target>
 
   <target name="dartc.jar" depends="compile" description="Creates a jar for dartc without bundling the dependencies.">
     <jar destfile="${dartc.jar}" basedir="${build.classes.dir}" manifest="dartc.mf"/>
   </target>
 
-  <target name="syslib" depends="corelib.jar,domlib.jar,htmllib.jar,jsonlib.jar" description="Stub for system library task">
+  <target name="syslib" depends="corelib.jar,domlib.jar,htmllib.jar,jsonlib.jar,isolatelib.jar" description="Stub for system library task">
     <!--
       Copy the system library jars to the lib folder.
     -->
     <copy file="${corelib.jar}" todir="${dist.dir}/lib"/>
     <copy file="${domlib.jar}" todir="${dist.dir}/lib"/>
     <copy file="${htmllib.jar}" todir="${dist.dir}/lib"/>
     <copy file="${jsonlib.jar}" todir="${dist.dir}/lib"/>
+    <copy file="${isolatelib.jar}" todir="${dist.dir}/lib"/>
 
     <touch file="${build.dir}/syslib.stamp"/>
   </target>
 
   <target name="syslib_clean" description="Clean out the system libraries">
     <delete file="${build.dir}/syslib.stamp"/>
   </target>
 
   <target name="dist" depends="dartc.jar" description="Creates a directory that contains a standalone distribution for dartc.">
     <!--
       Ensure the necessary subdirectories exist.
     -->
     <mkdir dir="${dist.dir}/bin"/>
     <mkdir dir="${dist.dir}/lib"/>
 
     <!--
       Copy the dart jar to the lib folder.
     -->
     <copy file="${dartc.jar}" todir="${dist.dir}/lib"/>
 
     <!--
       Re-root the classpaths from third_party into the lib folder of the distro.
     -->
     <pathconvert property="dartc.classpath.runtime.unix" targetos="unix" refid="classpath.runtime">
       <regexpmapper from="${third_party.dir}/(.*)" to="$DARTC_LIBS/\1"/>
     </pathconvert>
 
     <copy file="scripts/dartc.sh" tofile="${dist.dir}/bin/dartc">
       <filterset>
-        <filter token="CLASSPATH" value="$DARTC_LIBS/dartc.jar:$DARTC_LIBS/corelib.jar:$DARTC_LIBS/domlib.jar:$DARTC_LIBS/htmllib.jar:$DARTC_LIBS/jsonlib.jar:${dartc.classpath.runtime.unix}"/>
+        <filter token="CLASSPATH" value="$DARTC_LIBS/dartc.jar:$DARTC_LIBS/corelib.jar:$DARTC_LIBS/domlib.jar:$DARTC_LIBS/htmllib.jar:$DARTC_LIBS/jsonlib.jar:$DARTC_LIBS/isolatelib.jar:${dartc.classpath.runtime.unix}"/>
       </filterset>
     </copy>
     <chmod file="${dist.dir}/bin/dartc" perm="a+rx"/>
 
     <copy file="scripts/dartc_test.sh" tofile="${dist.dir}/bin/dartc_test">
       <filterset>
-        <filter token="CLASSPATH" value="$DARTC_LIBS/dartc.jar:$DARTC_LIBS/corelib.jar:$DARTC_LIBS/domlib.jar:$DARTC_LIBS/htmllib.jar:$DARTC_LIBS/jsonlib.jar:${dartc.classpath.runtime.unix}"/>
+        <filter token="CLASSPATH" value="$DARTC_LIBS/dartc.jar:$DARTC_LIBS/corelib.jar:$DARTC_LIBS/domlib.jar:$DARTC_LIBS/htmllib.jar:$DARTC_LIBS/jsonlib.jar:$DARTC_LIBS/isolatelib.jar:${dartc.classpath.runtime.unix}"/>
         <filter token="D8_EXEC" value="${d8}"/>
       </filterset>
     </copy>
     <chmod file="${dist.dir}/bin/dartc_test" perm="a+rx"/>
 
    <!--
       TODO: The following files are not strictly due to dist, move them out.
     -->
     <copy todir="${build.dir}">
       <fileset dir="scripts">
         <include name="dartc_run.sh"/>
         <include name="dartc_size.sh"/>
         <include name="dartc_metrics.sh"/>
       </fileset>
       <filterset>
-        <filter token="CLASSPATH" value="$DARTC_LIBS/dartc.jar:$DARTC_LIBS/corelib.jar:$DARTC_LIBS/domlib.jar:$DARTC_LIBS/htmllib.jar:$DARTC_LIBS/jsonlib.jar:${dartc.classpath.runtime.unix}"/>
+        <filter token="CLASSPATH" value="$DARTC_LIBS/dartc.jar:$DARTC_LIBS/corelib.jar:$DARTC_LIBS/domlib.jar:$DARTC_LIBS/htmllib.jar:$DARTC_LIBS/jsonlib.jar:$DARTC_LIBS/isolatelib.jar:${dartc.classpath.runtime.unix}"/>
       </filterset>
     </copy>
     <chmod file="${build.dir}/dartc_run.sh" perm="a+rx"/>
     <chmod file="${build.dir}/dartc_size.sh" perm="a+rx"/>
     <chmod file="${build.dir}/dartc_metrics.sh" perm="a+rx"/>
 
     <!--
       Copy of all of the dartc dependencies to the lib folder.
     -->
     <copy todir="${dist.dir}/lib">
       <path refid="classpath.runtime"/>
       <regexpmapper from="${third_party.dir}/(.*)" to="\1"/>
     </copy>
   </target>
 
   <target name="clean" description="Deletes the build output directory.">
     <delete dir="${build.dir}"/>
     <delete dir="${dist.dir}"/>
   </target>
 
   <target name="tests.jar" depends="compile-tests">
     <jar destfile="${build.dir}/tests.jar" basedir="${build.test.classes.dir}"/>
   </target>
 </project>