base: Disable trace event

This allows builds with enable_base_tracing=false.

src/base/trace_event/base_tracing_forward.h

@@ -10,7 +10,7 @@
 
 #include "base/tracing_buildflags.h"
 
-#if BUILDFLAG(ENABLE_BASE_TRACING)
+#if 1
 #include "third_party/perfetto/include/perfetto/tracing/traced_value_forward.h"  // nogncheck
 #else
 

src/base/trace_event/memory_allocator_dump.h

@@ -5,6 +5,8 @@
 #ifndef BASE_TRACE_EVENT_MEMORY_ALLOCATOR_DUMP_H_
 #define BASE_TRACE_EVENT_MEMORY_ALLOCATOR_DUMP_H_
 
+#include "base/trace_event/trace_event_stub.h"
+#if 0
 #include <stdint.h>
 
 #include <iosfwd>
@@ -159,4 +161,5 @@ void BASE_EXPORT PrintTo(const MemoryAllocatorDump::Entry&, std::ostream*);
 }  // namespace trace_event
 }  // namespace base
 
+#endif
 #endif  // BASE_TRACE_EVENT_MEMORY_ALLOCATOR_DUMP_H_

src/base/trace_event/memory_dump_manager.h

@@ -5,6 +5,8 @@
 #ifndef BASE_TRACE_EVENT_MEMORY_DUMP_MANAGER_H_
 #define BASE_TRACE_EVENT_MEMORY_DUMP_MANAGER_H_
 
+#include "base/trace_event/trace_event_stub.h"
+#if 0
 #include <stdint.h>
 
 #include <map>
@@ -267,4 +269,5 @@ class BASE_EXPORT MemoryDumpManager {
 }  // namespace trace_event
 }  // namespace base
 
+#endif
 #endif  // BASE_TRACE_EVENT_MEMORY_DUMP_MANAGER_H_

src/base/trace_event/memory_dump_provider.h

@@ -5,6 +5,8 @@
 #ifndef BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_
 #define BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_
 
+#include "base/trace_event/trace_event_stub.h"
+#if 0
 #include "base/base_export.h"
 #include "base/process/process_handle.h"
 #include "base/trace_event/memory_dump_request_args.h"
@@ -48,4 +50,5 @@ class BASE_EXPORT MemoryDumpProvider {
 }  // namespace trace_event
 }  // namespace base
 
+#endif
 #endif  // BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_

src/base/trace_event/process_memory_dump.h

@@ -5,6 +5,8 @@
 #ifndef BASE_TRACE_EVENT_PROCESS_MEMORY_DUMP_H_
 #define BASE_TRACE_EVENT_PROCESS_MEMORY_DUMP_H_
 
+#include "base/trace_event/trace_event_stub.h"
+#if 0
 #include <stddef.h>
 
 #include <map>
@@ -297,4 +299,5 @@ class BASE_EXPORT ProcessMemoryDump {
 }  // namespace trace_event
 }  // namespace base
 
+#endif
 #endif  // BASE_TRACE_EVENT_PROCESS_MEMORY_DUMP_H_

src/base/trace_event/trace_event.h

@@ -5,6 +5,8 @@
 #ifndef BASE_TRACE_EVENT_TRACE_EVENT_H_
 #define BASE_TRACE_EVENT_TRACE_EVENT_H_
 
+#include "base/trace_event/trace_event_stub.h"
+#if 0
 // This header file defines implementation details of how the trace macros in
 // trace_event_common.h collect and store trace events. Anything not
 // implementation-specific should go in trace_event_common.h instead of here.
@@ -805,4 +807,5 @@ class TraceScopedTrackableObject {
 }  // namespace trace_event
 }  // namespace base
 
+#endif
 #endif  // BASE_TRACE_EVENT_TRACE_EVENT_H_

src/base/trace_event/trace_event_stub.cc

@@ -6,6 +6,7 @@
 
 #include <string>
 
+#include "base/trace_event/memory_usage_estimator.h"
 #include "base/trace_event/trace_event_stub.h"
 
 namespace base {
@@ -20,6 +21,9 @@ MemoryDumpProvider::~MemoryDumpProvider() = default;
 // static
 constexpr const char* const MemoryDumpManager::kTraceCategory;
 
+template size_t EstimateMemoryUsage(const std::string&);
+template size_t EstimateMemoryUsage(const std::u16string&);
+
 }  // namespace trace_event
 }  // namespace base
 

src/base/trace_event/trace_event_stub.h

@@ -11,6 +11,8 @@
 #include <string>
 
 #include "base/base_export.h"
+#include "base/check.h"
+#include "base/memory/ref_counted.h"
 #include "base/strings/string_piece.h"
 #include "base/trace_event/common/trace_event_common.h"
 #include "base/trace_event/memory_allocator_dump_guid.h"
@@ -172,6 +174,41 @@ class BASE_EXPORT MemoryDumpProvider {
   MemoryDumpProvider() = default;
 };
 
+class BASE_EXPORT MemoryAllocatorDump {
+ public:
+  static constexpr char* kNameSize = nullptr;
+  static constexpr char* kNameObjectCount = nullptr;
+  static constexpr char* kUnitsBytes = nullptr;
+  static constexpr char* kUnitsObjects = nullptr;
+  static constexpr char* kTypeScalar = nullptr;
+  static constexpr char* kTypeString = nullptr;
+  void AddScalar(const char* name, const char* units, uint64_t value) {}
+  void AddString(const char* name,
+                 const char* units,
+                 const std::string& value) {}
+  const std::string& absolute_name() const { return absolute_name_; }
+  const MemoryAllocatorDumpGuid& guid() const { return guid_; }
+
+ private:
+  const std::string absolute_name_;
+  MemoryAllocatorDumpGuid guid_;
+};
+
+class BASE_EXPORT ProcessMemoryDump {
+ public:
+  MemoryAllocatorDump* CreateAllocatorDump(const std::string& absolute_name) {
+    CHECK(false);
+    return nullptr;
+  }
+  MemoryAllocatorDump* GetAllocatorDump(
+      const std::string& absolute_name) const {
+    CHECK(false);
+    return nullptr;
+  }
+  void AddOwnershipEdge(const MemoryAllocatorDumpGuid& source,
+                        const MemoryAllocatorDumpGuid& target) {}
+};
+
 class BASE_EXPORT MemoryDumpManager {
  public:
   static constexpr const char* const kTraceCategory =

src/net/BUILD.gn

@@ -670,8 +670,6 @@ component("net") {
     "log/net_log_values.h",
     "log/net_log_with_source.cc",
     "log/net_log_with_source.h",
-    "log/trace_net_log_observer.cc",
-    "log/trace_net_log_observer.h",
     "nqe/cached_network_quality.cc",
     "nqe/cached_network_quality.h",
     "nqe/connectivity_monitor.cc",