Fix free memory calculation.

base/process/process_metrics_linux.cc

Index: base/process/process_metrics_linux.cc
diff --git a/base/process/process_metrics_linux.cc b/base/process/process_metrics_linux.cc
index b14aa210bd57af5bd53c6581590fa221f355d9bb..1513f71f2536e073d02c4493e67d607f783b784c 100644
--- a/base/process/process_metrics_linux.cc
+++ b/base/process/process_metrics_linux.cc
@@ -535,9 +535,7 @@ const size_t kDiskWeightedIOTime = 13;
 SystemMemoryInfoKB::SystemMemoryInfoKB() {
   total = 0;
   free = 0;
-#if defined(OS_LINUX)
   available = 0;
-#endif
   buffers = 0;
   cached = 0;
   active_anon = 0;
@@ -547,6 +545,7 @@ SystemMemoryInfoKB::SystemMemoryInfoKB() {
   swap_total = 0;
   swap_free = 0;
   dirty = 0;
+  reclaimable = 0;
 
   pswpin = 0;
   pswpout = 0;
@@ -568,9 +567,7 @@ std::unique_ptr<Value> SystemMemoryInfoKB::ToValue() const {
 
   res->SetInteger("total", total);
   res->SetInteger("free", free);
-#if defined(OS_LINUX)
   res->SetInteger("available", available);
-#endif
   res->SetInteger("buffers", buffers);
   res->SetInteger("cached", cached);
   res->SetInteger("active_anon", active_anon);
@@ -581,6 +578,7 @@ std::unique_ptr<Value> SystemMemoryInfoKB::ToValue() const {
   res->SetInteger("swap_free", swap_free);
   res->SetInteger("swap_used", swap_total - swap_free);
   res->SetInteger("dirty", dirty);
+  res->SetInteger("reclaimable", reclaimable);
   res->SetInteger("pswpin", pswpin);
   res->SetInteger("pswpout", pswpout);
   res->SetInteger("pgmajfault", pgmajfault);
@@ -628,10 +626,8 @@ bool ParseProcMeminfo(const std::string& meminfo_data,
       target = &meminfo->total;
     else if (tokens[0] == "MemFree:")
       target = &meminfo->free;
-#if defined(OS_LINUX)
     else if (tokens[0] == "MemAvailable:")
       target = &meminfo->available;
-#endif
     else if (tokens[0] == "Buffers:")
       target = &meminfo->buffers;
     else if (tokens[0] == "Cached:")
@@ -650,6 +646,8 @@ bool ParseProcMeminfo(const std::string& meminfo_data,
       target = &meminfo->swap_free;
     else if (tokens[0] == "Dirty:")
       target = &meminfo->dirty;
+    else if (tokens[0] == "SReclaimable:")
+      target = &meminfo->reclaimable;
 #if defined(OS_CHROMEOS)
     // Chrome OS has a tweaked kernel that allows us to query Shmem, which is
     // usually video memory otherwise invisible to the OS.