GYP: fix compile flake for second-hand use of generated headers.

mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi

Index: mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi
diff --git a/mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi b/mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi
index 68348fb4bc7484625ded06d2ee32f35ab8de7603..ff7356ffaf8df4da6c95dadf47b588f27ab8b898 100644
--- a/mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi
+++ b/mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi
@@ -10,9 +10,11 @@
     'mojom_base_output_dir':
         '<!(python <(DEPTH)/build/inverse_depth.py <(DEPTH))',
     'mojom_generated_outputs': [
-      '<!@(python <(DEPTH)/mojo/public/tools/bindings/mojom_list_outputs.py --basedir <(mojom_base_output_dir) <@(mojom_files))',
+        '<!@(python <(DEPTH)/mojo/public/tools/bindings/mojom_list_outputs.py --basedir <(mojom_base_output_dir) <@(mojom_files))',
     ],
   },
+  # Prevent the generated sources from being injected into the "all" target.
+  #'suppress_wildcard': '1',
   'actions': [
     {
       'action_name': '<(_target_name)_mojom_bindings_generator',
@@ -39,10 +41,11 @@
         '--java_output_directory=<(java_out_dir)',
       ],
       'message': 'Generating Mojo bindings from <@(mojom_files)',
-      'process_outputs_as_sources': 1,
     }
   ],
   'direct_dependent_settings': {
+    # A target directly depending on this action will compile the generated
+    # sources.
     'sources': [
       '<@(mojom_generated_outputs)',
     ],
@@ -51,6 +54,9 @@
       '<(DEPTH)',
       '<(SHARED_INTERMEDIATE_DIR)',
     ],
+    # Make sure the generated header files are available for any static library
+    # that depends on a static library that depends on this generator.
+    'hard_dependency': 1,
     'direct_dependent_settings': {
       # Include paths needed to find the generated header files and their
       # transitive dependancies when using the library.
@@ -65,5 +71,4 @@
       },
     }
   },
-  'hard_dependency': 1,
 }