Bug 1374908 - Remove --enable-systrace. r=glandium.

This option causes MOZ_USE_SYSTRACE to be defined. The only use of that is in
GeckoProfiler.h where it causes the PROFILER_PLATFORM_TRACING macro to set
android::ScopedTrace. But android::ScopedTrace was defined in widget/gonk/
which was recently removed, so this won't work any more.

Furthermore, all that android::ScopedTrace did was to do a pair of
atrace_{begin,end}() calls, which doesn't seem that useful.

toolkit/moz.configure

@@ -9,19 +9,6 @@
 # ==============================================================
 # Some of the options here imply an option from js/moz.configure,
 # so, need to be declared before the include.
-option('--enable-systrace', env='MOZ_USE_SYSTRACE',
-       help='Turn on systrace for the Gecko profiler on android/b2g')
-
-@depends('--enable-systrace', target)
-def systrace(value, target):
-    if value and target.os != 'Android':
-        die('--enable-systrace cannot be used when targeting %s',
-            target.os)
-    if value:
-        return True
-
-set_define('MOZ_USE_SYSTRACE', systrace)
-
 
 option('--enable-jprof', env='MOZ_JPROF',
        help='Enable jprof profiling tool (needs mozilla/tools/jprof)')

tools/profiler/public/GeckoProfiler.h

@@ -57,38 +57,6 @@ using UniqueProfilerBacktrace =
 #define PROFILER_FUNC(decl, rv)  decl;
 #define PROFILER_FUNC_VOID(decl) void decl;
 
-// Uncomment this to turn on systrace or build with
-// ac_add_options --enable-systace
-//#define MOZ_USE_SYSTRACE
-#ifdef MOZ_USE_SYSTRACE
-# ifndef ATRACE_TAG
-#  define ATRACE_TAG ATRACE_TAG_ALWAYS
-# endif
-// We need HAVE_ANDROID_OS to be defined for Trace.h.
-// If its not set we will set it temporary and remove it.
-# ifndef HAVE_ANDROID_OS
-#  define HAVE_ANDROID_OS
-#  define REMOVE_HAVE_ANDROID_OS
-# endif
-// Android source code will include <cutils/trace.h> before this. There is no
-// HAVE_ANDROID_OS defined in Firefox OS build at that time. Enabled it globally
-// will cause other build break. So atrace_begin and atrace_end are not defined.
-// It will cause a build-break when we include <utils/Trace.h>. Use undef
-// _LIBS_CUTILS_TRACE_H will force <cutils/trace.h> to define atrace_begin and
-// atrace_end with defined HAVE_ANDROID_OS again. Then there is no build-break.
-# undef _LIBS_CUTILS_TRACE_H
-# include <utils/Trace.h>
-# define PROFILER_PLATFORM_TRACING(name) \
-    android::ScopedTrace \
-    PROFILER_APPEND_LINE_NUMBER(scopedTrace)(ATRACE_TAG, name);
-# ifdef REMOVE_HAVE_ANDROID_OS
-#  undef HAVE_ANDROID_OS
-#  undef REMOVE_HAVE_ANDROID_OS
-# endif
-#else
-# define PROFILER_PLATFORM_TRACING(name)
-#endif
-
 #define PROFILER_APPEND_LINE_NUMBER_PASTE(id, line) id ## line
 #define PROFILER_APPEND_LINE_NUMBER_EXPAND(id, line) \
   PROFILER_APPEND_LINE_NUMBER_PASTE(id, line)
@@ -108,7 +76,6 @@ using UniqueProfilerBacktrace =
 // Use PROFILER_LABEL_DYNAMIC if you want to add additional / dynamic
 // information to the pseudo stack frame.
 #define PROFILER_LABEL(name_space, info, category) \
-  PROFILER_PLATFORM_TRACING(name_space "::" info) \
   mozilla::AutoProfilerLabel \
   PROFILER_APPEND_LINE_NUMBER(profiler_raii)(name_space "::" info, nullptr, \
                                              __LINE__, category)
@@ -116,7 +83,6 @@ using UniqueProfilerBacktrace =
 // Similar to PROFILER_LABEL, PROFILER_LABEL_FUNC will push/pop the enclosing
 // functon name as the pseudostack label.
 #define PROFILER_LABEL_FUNC(category) \
-  PROFILER_PLATFORM_TRACING(PROFILER_FUNCTION_NAME) \
   mozilla::AutoProfilerLabel \
   PROFILER_APPEND_LINE_NUMBER(profiler_raii)(PROFILER_FUNCTION_NAME, nullptr, \
                                              __LINE__, category)
@@ -138,7 +104,6 @@ using UniqueProfilerBacktrace =
 // PROFILER_LABEL frames take up considerably less space in the profile buffer
 // than PROFILER_LABEL_DYNAMIC frames.
 #define PROFILER_LABEL_DYNAMIC(name_space, info, category, dynamicStr) \
-  PROFILER_PLATFORM_TRACING(name_space "::" info) \
   mozilla::AutoProfilerLabel \
   PROFILER_APPEND_LINE_NUMBER(profiler_raii)(name_space "::" info, dynamicStr, \
                                              __LINE__, category)