Summary:
- port D1840 to Dragonwell
- add AJVM_FLAGS extension flag

Test Plan: the other patches which add new VM flags will definitely cover this code change

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D849610

Summary:
- Port D336179 mini-heapdump support to Dragonwell
- Enable HotSpot to skip dumping content of primitive type arrays

Test Plan: hotspot/test/serviceability, jdk/test/ras

Reviewers: 井桐

Reviewed By: 井桐

Differential Revision: https://aone.alibaba-inc.com/code/D849312

Summary:
- Port fix D2553 to Dragonwell
- Change default GC policy to UseConcMarkSweepGC

Test Plan: hotspot/test/gc/TestDefaultGC.sh

Reviewers: 井桐

Reviewed By: 井桐

Subscribers:

Differential Revision: https://aone.alibaba-inc.com/code/D849276

Reviewers: 效山, 芳玺, 传胜, 三红, yumin.qi

Reviewed By: 三红, 芳玺, 效山, 卓仁

Differential Revision: https://aone.alibaba-inc.com/code/D815657

Reviewed-by: phh, mbalao, bae

Reviewed-by: kbarrett, tschatzl

Reviewed-by: lancea, clanger, andrew

Reviewed-by: serb, dmarkov, andrew

8202884: SA: Attach/detach might fail on Linux if debugee application create/destroy threads during attaching
Summary: While doing a ptrace attach, do not attach to threads which are in the process of exiting or are zombies -- skip these threads.
Reviewed-by: jcbeyler, ysuenaga

Reviewed-by: goetz, mdoerr
Contributed-by: NKazunori Ogata <ogatak@jp.ibm.com>

Summary: Change copyright date from 2017 to 2018.
Reviewed-by: andrew

Reviewed-by: sla, kbarrett, gziemski

Reviewed-by: thartmann, kvn

Summary: Prevent downgraded compilation tasks from recompiling.
Reviewed-by: sgehwolf, thartmann, andrew

Summary: Includes compile_id addition from JDK-8054492
Reviewed-by: andrew

Reviewed-by: prr

Reviewed-by: mdoerr, goetz
Contributed-by: NGustavo Serra Scalet &lt;gustavo.scalet@eldorado.org.br&gt;, Kazunori Ogata <ogatak@jp.ibm.com>

Summary: Avoided collecting unaligned stores in Initialize node by making can_capture_store return false for same
Reviewed-by: dlong, kvn, vlivanov

Reviewed-by: clanger

Reviewed-by: simonis, mdoerr
Contributed-by: NMichihiro Horie <horie@jp.ibm.com>

Summary: implement os::set_native_thread_name() on windows, linux
Reviewed-by: sla, ctornqvi, simonis
Contributed-by: thomas.stuefe@sap.com

Reviewed-by: phh

Reviewed-by: jbachorik

Summary: Compile with -O3 and relevant C flags as for fdlibm.
Reviewed-by: andrew

Summary: Add hotspot/test/runtime/jni directory with two tests for 8176100
Reviewed-by: kbarrett, coleenp, tschatzl

Summary: Add tag bit to all JNI weak handles
Reviewed-by: kbarrett, coleenp, tschatzl

Reviewed-by: dholmes

Reviewed-by: stuefe, tschatzl