Remove unnecessary indirection from MemMap.

Avoid plain MemMap pointers being passed around by changing
the MemMap to moveable and return MemMap objects by value.
Previously we could have a valid zero-size MemMap but this
is now forbidden.

MemMap::RemapAtEnd() is changed to avoid the explicit call
to munmap(); mmap() with MAP_FIXED automatically removes
old mappings for overlapping regions.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: Pixel 2 XL boots.
Test: m test-art-target-gtest
Test: testrunner.py --target --optimizing
Change-Id: I12bd453c26a396edc20eb141bfd4dad20923f170

1 files changed, 1 insertions, 1 deletions

diff --git a/compiler/common_compiler_test.h b/compiler/common_compiler_test.h
index db38110400..366489c58f 100644
--- a/compiler/common_compiler_test.h
+++ b/compiler/common_compiler_test.h
@@ -115,7 +115,7 @@ class CommonCompilerTest : public CommonRuntimeTest {
   std::unique_ptr<CompilerDriver> compiler_driver_;
 
  private:
-  std::unique_ptr<MemMap> image_reservation_;
+  MemMap image_reservation_;
 
   // Chunks must not move their storage after being created - use the node-based std::list.
   std::list<std::vector<uint8_t>> header_code_and_maps_chunks_;