Revert of Implement ScopedFD in terms of ScopedGeneric. (https://codereview.chromium.org/191673003/)

Reason for revert:
Doesn't build on android:

FAILED: /mnt/data/b/build/goma/gomacc ../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/base/memory/base.discardable_memory_allocator_android.o.d -DV8_DEPRECATION_WARNINGS -DBLINK_SCALE_FILTERS_AT_RECORD_TIME -D_FILE_OFFSET_BITS=64 -DNO_TCMALLOC -DDISABLE_NACL -DCHROMIUM_BUILD -DCOMPONENT_BUILD -DUSE_LIBJPEG_TURBO=1 -DENABLE_WEBRTC=1 -DUSE_PROPRIETARY_CODECS -DENABLE_CONFIGURATION_POLICY -DENABLE_NEW_GAMEPAD_API=1 -DDISCARDABLE_MEMORY_ALWAYS_SUPPORTED_NATIVELY -DSYSTEM_NATIVELY_SIGNALS_MEMORY_PRESSURE -DENABLE_EGLIMAGE=1 -DENABLE_AUTOFILL_DIALOG=1 -DCLD_VERSION=1 -DENABLE_PRINTING=1 -DENABLE_MANAGED_USERS=1 -DUSE_OPENSSL=1 -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -DBASE_IMPLEMENTATION -DANDROID -D__GNU_SOURCE=1 -DUSE_STLPORT=1 -D_STLP_USE_PTR_SPECIALIZATIONS=1 '-DCHROME_BUILD_ID=""' -DHAVE_SYS_UIO_H -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DWTF_USE_DYNAMIC_ANNOTATIONS=1 -D_DEBUG -Igen/base -I../../third_party/android_tools/ndk/sources/android/cpufeatures -I../.. -fstack-protector --param=ssp-buffer-size=4 -Werror -fno-exceptions -fno-strict-aliasing -Wall -Wno-unused-parameter -Wno-missing-field-initializers -fvisibility=hidden -pipe -fPIC -Wheader-hygiene -Wno-char-subscripts -Wno-unneeded-internal-declaration -Wno-covered-switch-default -Wstring-conversion -Wno-c++11-narrowing -Wno-reserved-user-defined-literal -Wno-deprecated-register -Xclang -load -Xclang /mnt/data/b/build/slave/Android_Clang_Builder__dbg_/build/src/tools/clang/scripts/../../../third_party/llvm-build/Release+Asserts/lib/libFindBadConstructs.so -Xclang -add-plugin -Xclang find-bad-constructs -Xclang -plugin-arg-find-bad-constructs -Xclang check-url-directory -fcolor-diagnostics -Wexit-time-destructors -march=armv7-a -mfpu=vfpv3-d16 -mfloat-abi=softfp -mthumb -no-integrated-as -B/mnt/data/b/build/slave/Android_Clang_Builder__dbg_/build/src/third_party/android_tools/ndk//toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin -ffunction-sections -funwind-tables -g -fstack-protector -fno-short-enums -Wa,--noexecstack -D__compiler_offsetof=__builtin_offsetof -Dnan=__builtin_nan -target arm-linux-androideabi -mllvm -arm-enable-ehabi --sysroot=/mnt/data/b/build/slave/Android_Clang_Builder__dbg_/build/src/third_party/android_tools/ndk//platforms/android-14/arch-arm -I/mnt/data/b/build/slave/Android_Clang_Builder__dbg_/build/src/third_party/android_tools/ndk//sources/cxx-stl/stlport/stlport -Os -g -fomit-frame-pointer -fdata-sections -ffunction-sections -funwind-tables -g0 -fno-rtti -fno-threadsafe-statics -fvisibility-inlines-hidden -Wsign-compare -std=gnu++11 -Wno-implicit-exception-spec-mismatch -Wno-abi  -c ../../base/memory/discardable_memory_allocator_android.cc -o obj/base/memory/base.discardable_memory_allocator_android.o
../../base/memory/discardable_memory_allocator_android.cc:84:25:error: no matching function for call to 'mmap'
  void* const address = mmap(
                        ^~~~
/mnt/data/b/build/slave/Android_Clang_Builder__dbg_/build/src/third_party/android_tools/ndk//platforms/android-14/arch-arm/usr/include/sys/mman.h:47:15: note: candidate function not viable: no known conversion from 'base::ScopedFD' (aka 'ScopedGeneric<int, internal::ScopedFDCloseTraits>') to 'int' for 5th argument
extern void*  mmap(void *, size_t, int, int, int, off_t);
              ^
1 error generated.

Original issue's description:
> Implement ScopedFD in terms of ScopedGeneric.
> 
> Move to a new file base/files/scoped_file.h. I will also add ScopedFILE to here (currently in file_util.h) later.
> 
> I think there is a crash in the old code in content/browser/zygote_host/zygote_host_impl_linux.cc that this patch should fix. The old ScopedFD took the address of something in a vector that is being modified.
> 
> I removed SafeScopedFD from content/common/sandbox_linux/sandbox_linux.cc since base's ScopedFD not CHECKs on close failure (this is a more recent addition).
> 
> BUG=
> R=agl@chromium.org, viettrungluu@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=257001

TBR=viettrungluu@chromium.org,agl@chromium.org,brettw@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/197873014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@257005 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 13 insertions, 10 deletions

diff --git a/tools/android/memdump/memdump.cc b/tools/android/memdump/memdump.cc
index 4f4dd14..20684f6 100644
--- a/tools/android/memdump/memdump.cc
+++ b/tools/android/memdump/memdump.cc
@@ -22,7 +22,6 @@
 #include "base/callback_helpers.h"
 #include "base/containers/hash_tables.h"
 #include "base/file_util.h"
-#include "base/files/scoped_file.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
@@ -437,12 +436,13 @@ bool CollectProcessMemoryInformation(int page_count_fd,
                                      int page_flags_fd,
                                      ProcessMemory* process_memory) {
   const pid_t pid = process_memory->pid;
-  base::ScopedFD pagemap_fd(open(
-      base::StringPrintf("/proc/%d/pagemap", pid).c_str(), O_RDONLY));
-  if (!pagemap_fd.is_valid()) {
+  int pagemap_fd = open(
+      base::StringPrintf("/proc/%d/pagemap", pid).c_str(), O_RDONLY);
+  if (pagemap_fd < 0) {
     PLOG(ERROR) << "open";
     return false;
   }
+  file_util::ScopedFD auto_closer(&pagemap_fd);
   std::vector<MemoryMap>* const process_maps = &process_memory->memory_maps;
   if (!GetProcessMaps(pid, process_maps))
     return false;
@@ -450,7 +450,7 @@ bool CollectProcessMemoryInformation(int page_count_fd,
        it != process_maps->end(); ++it) {
     std::vector<PageInfo>* const committed_pages = &it->committed_pages;
     BitSet* const pages_bits = &it->committed_pages_bits;
-    GetPagesForMemoryMap(pagemap_fd.get(), *it, committed_pages, pages_bits);
+    GetPagesForMemoryMap(pagemap_fd, *it, committed_pages, pages_bits);
     SetPagesInfo(page_count_fd, page_flags_fd, committed_pages);
   }
   return true;
@@ -489,18 +489,21 @@ int main(int argc, char** argv) {
 
   std::vector<ProcessMemory> processes_memory(pids.size());
   {
-    base::ScopedFD page_count_fd(open("/proc/kpagecount", O_RDONLY));
-    if (!page_count_fd.is_valid()) {
+    int page_count_fd = open("/proc/kpagecount", O_RDONLY);
+    if (page_count_fd < 0) {
       PLOG(ERROR) << "open /proc/kpagecount";
       return EXIT_FAILURE;
     }
 
-    base::ScopedFD page_flags_fd(open("/proc/kpageflags", O_RDONLY));
-    if (!page_flags_fd.is_valid()) {
+    int page_flags_fd = open("/proc/kpageflags", O_RDONLY);
+    if (page_flags_fd < 0) {
       PLOG(ERROR) << "open /proc/kpageflags";
       return EXIT_FAILURE;
     }
 
+    file_util::ScopedFD page_count_fd_closer(&page_count_fd);
+    file_util::ScopedFD page_flags_fd_closer(&page_flags_fd);
+
     base::ScopedClosureRunner auto_resume_processes(
         base::Bind(&KillAll, pids, SIGCONT));
     KillAll(pids, SIGSTOP);
@@ -510,7 +513,7 @@ int main(int argc, char** argv) {
           &processes_memory[it - pids.begin()];
       process_memory->pid = *it;
       if (!CollectProcessMemoryInformation(
-              page_count_fd.get(), page_flags_fd.get(), process_memory)) {
+              page_count_fd, page_flags_fd, process_memory)) {
         return EXIT_FAILURE;
       }
     }