Use faster, but less information methods to calculate memory dumps on macOS.

base/process/process_metrics.h

Index: base/process/process_metrics.h
diff --git a/base/process/process_metrics.h b/base/process/process_metrics.h
index 1562e7b156af082292b3c8a4753a4b26fb7ecfcd..9c1ea9d9281dea2f780b2d6375806888b2b68a61 100644
--- a/base/process/process_metrics.h
+++ b/base/process/process_metrics.h
@@ -25,6 +25,10 @@
 #if defined(OS_MACOSX)
 #include <mach/mach.h>
 #include "base/process/port_provider_mac.h"
+
+#if !defined(OS_IOS)
+#include <mach/mach_vm.h>
+#endif
 #endif
 
 #if defined(OS_WIN)
@@ -478,6 +482,42 @@ class SystemMetrics {
 #endif
 };
 
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+enum class MachVMRegionResult {
+  // There were no more memory regions between |address| and the end of the
+  // virtual address space.
+  Finished,
+
+  // All output parameters are invalid.
+  Error,
+
+  // All output parameters are filled in.
+  Success
+};
+
+// Returns info on the first memory region at or after |address|, including
+// resident memory and share mode. On Success, |size| reflects the size of the
+// memory region.
+// |size| and |info| are output parameters, only valid on Success.
+// |address| is an in-out parameter, than represents both the address to start
+// looking, and the start address of the memory region.
+BASE_EXPORT MachVMRegionResult GetTopInfo(mach_port_t task,
+                                          mach_vm_size_t* size,
+                                          mach_vm_address_t* address,
+                                          vm_region_top_info_data_t* info);
+
+// Returns info on the first memory region at or after |address|, including
+// protection values. On Success, |size| reflects the size of the
+// memory region.
+// Returns info on the first memory region at or after |address|, including
+// resident memory and share mode.
+// |size| and |info| are output parameters, only valid on Success.
+BASE_EXPORT MachVMRegionResult GetBasicInfo(mach_port_t task,
+                                            mach_vm_size_t* size,
+                                            mach_vm_address_t* address,
+                                            vm_region_basic_info_64* info);
+#endif  // defined(OS_MACOSX) && !defined(OS_IOS)
+
 }  // namespace base
 
 #endif  // BASE_PROCESS_PROCESS_METRICS_H_