Fix "unreachable code" warnings (MSVC warning 4702) in content/.

content/browser/gpu/compositor_util.cc

Index: content/browser/gpu/compositor_util.cc
===================================================================
--- content/browser/gpu/compositor_util.cc	(revision 256983)
+++ content/browser/gpu/compositor_util.cc	(working copy)
@@ -194,18 +194,16 @@
 
   // Command line switches take precedence over blacklist.
   if (command_line.HasSwitch(switches::kDisableForceCompositingMode) ||
-      command_line.HasSwitch(switches::kDisableThreadedCompositing)) {
+      command_line.HasSwitch(switches::kDisableThreadedCompositing))
     return false;
-  } else if (command_line.HasSwitch(switches::kEnableThreadedCompositing)) {
+  if (command_line.HasSwitch(switches::kEnableThreadedCompositing))
     return true;
-  }
 
 #if defined(USE_AURA) || defined(OS_MACOSX)
   // We always want threaded compositing on Aura and Mac (the fallback is a
   // threaded software compositor).
   return true;
-#endif
-
+#else
   if (!CanDoAcceleratedCompositing() || IsForceCompositingModeBlacklisted())
     return false;
 
@@ -214,9 +212,10 @@
   // The blacklist check above takes care of returning false before this hits
   // on unsupported Win versions.
   return true;
+#else
+  return false;
 #endif
-
-  return false;
+#endif
 }
 
 bool IsForceCompositingModeEnabled() {
@@ -229,7 +228,7 @@
   // Command line switches take precedence over blacklisting.
   if (command_line.HasSwitch(switches::kDisableForceCompositingMode))
     return false;
-  else if (command_line.HasSwitch(switches::kForceCompositingMode))
+  if (command_line.HasSwitch(switches::kForceCompositingMode))
     return true;
 
   if (!CanDoAcceleratedCompositing() || IsForceCompositingModeBlacklisted())
@@ -240,9 +239,9 @@
   // Mac OSX 10.8+ since M28. The blacklist check above takes care of returning
   // false before this hits on unsupported Win/Mac versions.
   return true;
+#else
+  return false;
 #endif
-
-  return false;
 }
 
 bool IsDelegatedRendererEnabled() {